ChemQuiz.net

Hello again, and welcome to November! In this newsletter, I’ve included the following important updates about ChemQuiz.net:

• *NEW* Aufbau diagrams added to Electron Configurations Quiz!
• *NEW* advanced options for nine quizzes!
• More new features, bug fixes and other improvements
• Site licenses for the ChemQuiz.net Dashboard

*NEW* Aufbau diagrams!

I’m really excited to announce the latest addition to ChemQuiz.net: Aufbau diagrams in the Electron Configurations Quiz!

Students can practice building Aufbau diagrams by clicking on the boxes to change them to one up arrow (↑), a pair of up and down arrows (⇅), or an empty box. For big elements with lots of electrons, students can use the “Check/uncheck all boxes” feature to make it easier to complete diagrams. You can also generate questions that only show the outer orbitals, which works better for multiple choice questions:

This is my first attempt at a completely graphic question style using JavaScript, so I’m pretty happy with how it turned out. Try it out and let me know what you think! I’d also love to hear if you have any suggestions for other diagram-based questions that would be useful to you and your students.

New advanced options for nine quizzes!

I get lots of requests from Chemistry teachers who want more control over the questions generated by the assignments they create for their students, and as a classroom teacher who has always been very picky about the materials I use, I completely understand! Since I created ChemQuiz.net, I’ve tried to balance giving users more options with keeping the quizzes easy to use by students.

To try to resolve this issue, I’ve created a number of “advanced options” that give teachers more control over their assignments. These options appear in the ChemQuiz.net Dashboard when you create an assignment, but are also accessible to teachers on the main page of each quiz, as long as they’re logged in. Here are some of the new advanced options that are available to use immediately:

• Average Atomic Masses Quiz – specify the number of isotopes in each problem, and only generate isotopes with whole number masses (thanks, Susan!)
• Density Calculations Quiz – specify the wanted value (D, m or V)
• Gas Laws Quiz – specify the wanted value (P1, P2, T1, T2, V1, V2, n, P, T or V)
• Laboratory Equipment Quiz – only show OSHA pictograms (thanks, Matthew!)
• Lewis Dot Structures Quiz – only generate Lewis structure questions with a single central atom (thanks, Debra!)
• Light & Energy Quiz – specify the wanted value (ν, λ, E, bond dissociation energy)
• Naming Compounds & Calculating Molar Masses Quiz – exclude compounds with Dy, Eu, Mn and U ions (thanks, Jason!)
• Periodic Trends Quiz – ignore exceptions and focus on the trend only (thanks, Patrisha and Andrew!)
• SI Conversions Quiz – exclude specific SI prefixes (thanks, Ryan!)

Remember, these advanced features are currently only available to teachers with an active site license for the ChemQuiz.net Dashboard. You can find out how to purchase a site license here, or you can sign up for a free 30-day demo by filling out this short form!

I hope these new features help you generate the kinds of questions you want for your students! If you have a suggestion for improving any of the quizzes on ChemQuiz.net, please send it to me, because I’m always interested in hearing what my fellow Chemistry teachers have to say.

More new features, bug fixes & other improvements

In addition to the new advanced features listed above, I’ve also made the following updates to the site:

Dashboard – these features and bug fixes also apply to PhysQuiz.net!

• bug fix: colleagues at the same school couldn’t see assignment previews (thanks, Ashley!)

All Quizzes

• new feature: students can no longer paste into answer boxes on quizzes

Average Atomic Masses Quiz

• correction: improved quality of fake atomic masses to make them more realistic (thanks, Matthew!)

Bond Polarity & Electronegativity Quiz

• correction: electronegativity value for Pb was incorrect (thanks, Lan!)

Density Calculations Quiz

• bug fix: answers were calculated using density values directly from the database instead of rounded values given in the problem (thanks, Elaine!)
• bug fix: density problems solving for mass or volume using kg/m³ and g/L were off by a factor of 1000 (thanks, Scott!)

Electron Configurations Quiz

• bug fix: “Load More Problems Like This” button caused quiz to crash due to referencing an empty array key
• bug fix: selecting multiple choice option could crash the quiz if elements 102-104 were randomly selected for problems
• correction: updated electron configuration of nickel to reflect research literature (now [Ar] 3d9 4s1)

Elements & Isotopes Quiz

• new feature: added questions to determine subatomic particles of ions (thanks, Michael, Shauna & Jillian!)

Naming Compounds & Calculating Molar Masses Quiz

• bug fix: some excluded ions were still showing up in questions (thanks, Pamela!)

• correction: added “hydrogen phosphate ion” and “hydrogen phosphite ion” as alternate names in the database for their respective ions (thanks, Scott!)
• correction: gallium is multivalent but didn’t have parentheses in its name (thanks again, Scott!)

Nuclear Reactions Quiz

• bug fix: student progress on multiple choice questions was not being saved (thanks, E!)
• correction: two beryllium beta decays were incorrectly producing beryllium daughter isotopes instead of boron (thanks, Matthew!)

Periodic Trends Quiz

• bug fix: new “simplify trends” option prevented displaying results because of missing array values (thanks, Andrew and Kasey!)

SI Conversions Quiz

• bug fix: Liter-to-gallon conversions weren’t calculating the correct answer (thanks, Scott!)

Significant Figures Quiz

• bug fix: answers for rounding problems that were less than 1 that were entered without a leading zero (e.g., .01) were being scored as incorrect (thanks, Scott!)

Types of Matter Quiz

• correction: changed justification question to “Best justification?” so that it’s clearer for students (thanks, Patrisha!)

Thanks again to everyone who has sent in a suggestion or reported a bug! Please let me know if you encounter any problems while using the site, because I want the site to be as bug-free as possible so that it works properly for everyone.

Site licenses for the ChemQuiz.net Dashboard

Thank you to the 153 schools and tutors who have purchased or renewed their site license for the ChemQuiz.net Dashboard for the 2024-2025 school year! Site licenses help me pay for the web hosting and software I use to write the quizzes, and it keeps the website ad-free. They also make it possible for me to spend time adding new features to the quizzes and the Dashboard.

With an active site license, you can:

• create assignments for your students using the quizzes on the site
• select the options you want that best match your students’ needs (e.g. ionic compounds only)
• use the “tab switch detection” anti-cheating feature
• review results with your students so they can correct misconceptions and grasp concepts more quickly
• track your students’ progress and download results for data analysis

If you’d like to purchase a yearly site license for just US$70, you can do so in any of the following ways:

• credit card through Square (the most popular option)
• school purchase order (contact me for a sales quote – I’m also happy to fill out any paperwork required by your institution or state)
• personal check
• CashApp, PayPal, Venmo or Zelle at chris@chemquiz.net

Additional schools in the same district can purchase an add-on license for 50% off at just US$35 per school. If your school offers physics, you can bundle a site license for the PhysQuiz.net Dashboard for just US$35 more! Please contact me if you have any questions about how to purchase a site license.

Site licenses also make it possible for me to make the ChemQuiz.net Dashboard free for 178 public schools in the United States where the majority of students are economically disadvantaged. If you teach in a high poverty public school (at least 50% of your students on free/reduced lunch or designated “economically disadvantaged”), please send me a link to the supporting documentation and you’ll get a free site license for the ChemQuiz.net Dashboard forever (PhysQuiz.net, too!).

Help me share ChemQuiz.net with the world!

If you like using ChemQuiz.net, there are three quick and easy things that you can do to help me promote the site!

• Add your school to the list of supporters on the About page! Simply go to the ChemQuiz.net Dashboard, click on “Your Info” in the top menu bar, activate the box next to “Display School on ChemQuiz.net“, and click the “Update Your Info” button.
• Tell another Chemistry teacher about ChemQuiz.net and encourage them to try out the Dashboard!
• Follow @ChemQuizDotNet on Facebook and Threads and share my updates with your fellow Chemistry teachers!

With Halloween, daylight saving time, and Election Day all within a week of each other, this can be a really challenging time to be in school! I hope you’re in a position where you can block out the noise and focus on the joy of sharing science with your students, although that’s easier for some than it is for others. Our society needs scientists and scientifically literate citizens, so what you’re doing matters – a lot!

Thanks again to everyone for all of your support, suggestions and feedback! Please use the Contact form or email me at chris@chemquiz.net if you ever have any questions, comments, or concerns. Take care, and to those of you in the United States, I hope you have a Happy Thanksgiving!

-Chris

Hi, everybody, I hope you’re doing well! In this newsletter, I’ve included the following important updates about ChemQuiz.net:

• *NEW* dimensional analysis problems added to SI Conversions Quiz!
• *NEW* ease-of-use features for the Dashboard!
• More new features, bug fixes and other improvements
• Site licenses for the 2024-2025 school year
• Request for donations to Asheville and Western North Carolina

*NEW* Dimensional analysis problems!

I’ve had a number of teachers ask me to add dimensional analysis and unit conversion problems to ChemQuiz.net, so that’s what I did! The rebranded SI Conversions & Dimensional Analysis Quiz has the following new problem types:

I know a lot of teachers have already covered dimensional analysis at this point of the year in their Chemistry classes, but I figured the new problem types could be used for review before an exam, and temperature and pressure conversions are necessary throughout the school year. Let me know if there are any additional conversions you’d like to see added to this quiz, and I’ll see what I can do!

New ease-of-use features!

Over the past month, I’ve tried to focus mainly on making ease-of-use improvements for the ChemQuiz.net as well as adding features to several quizzes so that they work better for teachers and their students. I wanted to highlight some new features that I hope you’ll like!

New option to auto-archive student results

Last month, I added a “Dashboard Settings” page that lets teachers set their own preferences for how to change how assignments are sorted for their students. This month, I added an “auto-archive” feature to help teachers keep their student results better organized! To activate it in the ChemQuiz.net Dashboard, go to Settings > Dashboard Settings, then check the box next to “Automatically archive student results two weeks after submission”:

If you select this option, every day at 5am Eastern Time, any student results that are at least 2 weeks old will be archived (but not deleted). This should help keep your Results page from getting out of control!

New filter menus on the Grades page

I also added filter menus to the Grades page that work just like the menus on the Results page:

Assignment link after creation or updating

One last new feature that I added should make it a little easier to share your assignments with your students. Immediately after you create or update an assignment, the share link appears at the top of the page:

I hope these new features make the ChemQuiz.net Dashboard easier to use and save you some time!

More new features, bug fixes & other improvements

As always, thanks to everyone who has submitted a suggestion or bug report for the site! Here are all of the updates I’ve made since the last newsletter:

Dashboard – these features and bug fixes also apply to PhysQuiz.net!

• new feature: option to auto-archive old results after two weeks
• new feature: link to share an assignment appears at top of page immediately after creating or updating that assignment
• enhancement: option to export all students, even if they don’t have any results (thanks, Zack!)
• enhancement: option to sort exported results by class and then by student name (thanks, Jason and Anna!)
• enhancement: add filter menus and page number links to the Grades page
• enhancement: added yellow highlight on Grades page for results that were submitted late (thanks, Elizabeth!)
• bug fix: couldn’t delete exam sections (thanks, Kenneth!)
• bug fix: couldn’t modify a student account if the same username was already in the users table, even if it was inactive or deleted (thanks, Lance!)
• bug fix: student Dashboard was trying to show resources for each exam section even if a section had no resources
• bug fix: an extra “Add another section” button was showing up when editing an exam
• bug fix: sort assignment tags alphabetically on Assignments page

All Quizzes

• new feature: can now show instructions above every question in Continuous mode (thanks, Maggie!)
• bug fix: quiz completion time would sometimes save without taking the student’s time zone into account, which would cause the time to be off by several hours (thanks, Racquel and Susan!)
• bug fix: time zone diagnostic information was showing at the bottom of quizzes for students completing assignments

Elements & Isotopes Quiz

• bug fix: un-initialized array was crashing the quiz when multiple choice options were generated (thanks, Lance!)
• bug fix: number of neutrons in U-236 was incorrect (thanks, Susan!)

Lewis Dot Structures Quiz

• bug fix: quiz would lose track of selected problem type(s) at the beginning when choosing Continuous mode (thanks, Pamela!)

Light & Energy Quiz

• new feature: advanced option* to restrict wavelengths to meters only (thanks, Helen!)

Molecular Geometry & VSEPR Quiz

• enhancement: added “(has dipole moment)” and “(no dipole moment)” to multiple choice options for polarity (thanks, Susan!)

Naming Compounds & Calculating Molar Masses Quiz

• new feature: advanced option* to exclude beryllium and carbide ions (thanks, Katharine!)

Percent Error & Percent Yield Quiz

• new feature: advanced option* to pick wanted quantities for problems (thanks, Rhonda and Caytee!)

Scientific Measurements Quiz

• new feature: option to generate grayscale diagrams for printing
• bug fix: problem types were being overwritten in Continuous mode

Scientific Notation Quiz

• new feature: advanced option* to generate problems with only positive or negative exponents

SI Conversions Quiz

• new feature: add dimensional analysis and other conversion problems to the SI Conversions Quiz & renamed it to the SI Conversions & Dimensional Analysis Quiz (thanks, Shauna, Andrew, Matt, Patrisha, and Zack!)
• new feature: add moles and candelas to SI Conversions Quiz (thanks, Joel!)
• bug fix: options for features that weren’t published yet were being used for assignments (thanks, Zack, Scott and Lauren!)
• bug fix: quiz was showing the wrong answer for SI conversions if previous answer was dimensional analysis (thanks, Lenora!)
• bug fix: inch-centimeter conversion was flipped (thanks again, Lenora!)

Significant Figures Quiz

• bug fix: answers in scientific notation weren’t being graded correctly (thanks, Rhonda!)
• bug fix: numbers in scientific notation were not being rounded with the correct number of sig figs (thanks, Avyukth and Rhonda!)
• bug fix: guesses for some division problems weren’t being graded correctly (thanks, Zack!)

Stoichiometry & Limiting Reagents Quiz

• enhancement: exclude reactions with Fe3O4 (thanks, Mary Ann!)

* advanced options are only available to teachers with an active site license for the ChemQuiz.net Dashboard

Thanks again to everyone who has sent in a suggestion or bug report! I try to fix bugs as quickly as possible, and I want to make the site as useful and easy to use as possible, so please let me know if you have a suggestion or bug report!

Site licenses for the 2024-2025 school year

Thank you to everyone who has purchased or renewed their school’s site license for the ChemQuiz.net Dashboard for the 2024-2025 school year! Site licenses help me pay for the web hosting and software I use to write the quizzes, and it keeps the website ad-free. In the month of September, ChemQuiz.net had over 2 million visits and exceeded 100,000 unique visitors in a single day several times, so your support has helped the site keep running while its popularity continues to grow!

If you would like to purchase a site license for the 2024-2025 school year for just US$70, you can do so right now in one of the following ways:

• credit card through Square (the most popular option)
• school purchase order (contact me for a sales quote – I’m also happy to fill out any paperwork required by your institution or state)
• personal check
• CashApp, PayPal, Venmo or Zelle at chris@chemquiz.net

Additional schools in the same district can purchase an add-on license for 50% off at just US$35 per school. If your school offers physics, you can bundle a site license for the PhysQuiz.net Dashboard for just US$35 more! Please contact me if you have any questions about how to purchase a site license.

Site licenses also help me offer the ChemQuiz.net Dashboard for free to 170 public schools in the United States where the majority of students are economically disadvantaged. If you teach in a high poverty public school (at least 50% of your students on free/reduced lunch or designated “economically disadvantaged”), please send me a link to the supporting documentation and you’ll get a free site license for the ChemQuiz.net Dashboard forever (PhysQuiz.net, too!).

Help me share ChemQuiz.net with the world!

If you like using ChemQuiz.net, there are three quick and easy things that you can do to help me promote the site!

• Add your school to the list of supporters on the About page! Simply go to the ChemQuiz.net Dashboard, click on “Your Info” in the top menu bar, activate the box next to “Display School on ChemQuiz.net“, and click the “Update Your Info” button.
• Tell another Chemistry teacher about ChemQuiz.net and encourage them to try out the Dashboard!
• Follow @ChemQuizDotNet on Facebook and Threads and share my updates with your fellow Chemistry teachers!

Hurricane Helene caused tremendous devastation to communities across the southeastern US, including Western North Carolina. My sister lives just outside Asheville, NC, and my niece and nephew both live in town, and fortunately, they’re all alive and uninjured. The pictures they’ve been sending to our family group chat of the damage caused by the historical flooding have been absolutely heartbreaking, and residents of the city probably won’t have running water for another 2-3 months.

Two local charities that my sister asked me to share are BeLoved Asheville and MANNA FoodBank, and 100% of donations go to help the people of Asheville and Western North Carolina. I’ve donated to both, so if you’re in a financial situation where you feel you’re able to donate, I’m sure these non-profit organizations and the people they serve would very much appreciate it.

I hope your school year is going well so far! Thanks again to everyone for all of your support, suggestions and feedback – I can’t tell you how much I appreciate it. Please use the Contact form or email me at chris@chemquiz.net if you have any questions, comments, or concerns. Take care!

-Chris

Hello again! I hope the school year has started smoothly for you and you have classes filled with students who are eager to learn Chemistry 😆. In this newsletter, I’ve included the following important updates about ChemQuiz.net:

• *NEW* Significant Figures Quiz problem type – rounding!
• *NEW* Dashboard features and improvements
• Quick tips on sharing classes with colleagues and differentiation
• Site licenses for the 2024-2025 school year
• Bug fixes and other improvements

*NEW* Sig fig rounding problems!

One of the very first quizzes I created for ChemQuiz.net was the Significant Figures Quiz, and it’s been popular from the very beginning. I’ve found that even my strongest students can struggle with trying to keep track of which digits matter in a number and why. To make this a little easier on everyone, I’ve added a new problem type – rounding!

In Chemistry, the reason we need to be able to count how many sig figs a number has is so that we can round a value properly after performing calculations, so my hope is that this problem type will help students learn how to do that. Here’s an example of some of the problems the quiz can generate:

In the ChemQuiz.net Dashboard, when you create an assignment using this quiz, you can choose whether or not you want it to generate problems using decimal and/or scientific notation. Personally, I like splitting those out into two separate mini-assignments for my students so that they can get the hang of it with decimal notation before I give them scientific notation (which is, in my opinion, easier).

I also added problem explanations for rounding by sig figs:

Try out the new rounding problems on the Significant Figures Quiz and let me know what you and your students think!

*NEW* Dashboard features!

I’ve also added some new features to the ChemQuiz.net Dashboard based on teacher feedback so that it’s easier to use for everyone.

New “Settings” menu

First, for better organization, I created a new “Settings” menu and moved “User Settings”, “Dashboard Settings”, and “School Info” under there:

New assignment order option

Also, teachers can now change the order in which their assignments appear on their students’ Dashboard! To change the order, go to Settings > Dashboard Settings:

You can change the display order directly on the Assignments page by selecting “Update order of assignment(s)” in the bulk actions menu and then using the dropdown menus in each row:

You can also change the assignment order when you’re creating or editing an assignment. I know that a lot of science teachers are highly organized and pay close attention to detail, so I apologize for not adding this feature four years ago when I first created ChemQuiz.net! Please note that this currently only changes the order in which assignments appear on your students’ Dashboard, not teachers (this feature is coming soon). Thanks to Don for this suggestion!

Display score percentage

You can now see score percentages on both the Results and Grades pages by hovering over a student score:

Thanks to Jana for the great suggestion!

“Helpful resource” links to free online textbook

When I created independent student accounts, I looked for a free, well-made online textbook that students could use to learn or review a topic before taking a practice quiz. After looking at numerous options, I felt that the LibreTexts textmap for “Chemistry: The Central Science” by Brown et al. was the most robust and complete, so I included links to specific chapters for each assignment that I’d created for those students.

To make everyone’s lives easier, I’ve now added a new feature for teachers to add these links to the top of assignments! Simply create a new assignment or edit one you’ve already made, and after you’ve selected the quiz-specific features, you’ll see an option like this:

In this example, these chapters are for the Balancing, Identifying & Predicting Chemical Equations Quiz. You can preview the chapters when you create or edit an assignment, or you can see all of the chapters for each quiz on the Quizzes page (you have to be logged in to your Dashboard account in order to see them). I know a lot of schools don’t hand out textbooks any more, and I’ve found that some online textbooks are nearly impossible to use, so I hope this resource helps!

Export results as “grid”

I also added the ability to export your score results as a CSV file in a “grid” format (like how they’re displayed on the Grades page):

This would be most useful for those of you who store your grades in a spreadsheet such as Excel or Google Sheets, or want more control over how they’re imported into your existing LMS. Thanks to Jason for this suggestion! Please note that the grid format will only export the highest score that a student earns for each assignment. (A number of you have reached out asking for automatic synchronization of results between the Dashboard and popular LMS’s such as Canvas and Google Classroom, so please know that I plan on adding that feature and I appreciate your patience while I figure that out.)

If you don’t have a site license for the ChemQuiz.net Dashboard but you want to try out these new features, please fill out this short Teacher Interest form for a free 30-day demo!

Finally, all of these new features are also available on PhysQuiz.net, so if you also teach Physics or have a colleague who might be interested in trying it out, please fill out the PhysQuiz.net Teacher Interest form for a free demo!

Quick tips: sharing classes & differentiation

I have two quick tips to make your lives easier! First, if you teach Chemistry with one or more colleagues and you want to synchronize your ChemQuiz.net assignments, you can easily share your classes with them. Simply create a new class or edit an existing one, and then check the boxes next to each colleague’s name at the bottom of the page:

Then, when your colleague creates an assignment, they can also assign it to your class, and you’ll be able to see student results and grades from those assignments just like you normally do. If you have several teachers at one school who want to synchronize like this, I recommend designating one person as the “lead” teacher, and then everyone else shares their classes with that lead teacher. The lead teacher can then create the assignments for everyone’s classes all at once, which I hope will save everyone lots of time!

Another quick tip is about differentiation, which is an easy term for administrators to toss around but can be a challenge for teachers to implement successfully. I taught Environmental Science and APES in a differentiated classroom for years, so I know this firsthand!

Students can be in more than one class in the ChemQuiz.net Dashboard, so you can differentiate for them by placing them in an additional “class” and then creating assignments that best match their abilities. For example, two years ago I had a few students who completed assignments on ChemQuiz.net very quickly, so I created an additional class just for them so I could assign them additional, more challenging assignments. Students can’t see what classes they’re in, only the assignments that are currently active for them and their past results.

You can create a special class by clicking on the Classes menu, clicking the pink “Create a Class” button, and then completing the form like you would for any other class:

Note that some of the students listed are already in another class, but adding them to this class won’t remove them from any other classes. This can also make it easier to differentiate for students who have IEPs or 504 Plans and receive accommodations or modifications, especially if you need to collect data showing how you’re supporting those plans.

Site licenses for the 2024-2025 school year

Thank you to everyone who has purchased or renewed their school’s site license for the ChemQuiz.net Dashboard for the 2024-2025 school year! Site licenses help me pay for the web hosting and software I use to write the quizzes, and it keeps the website ad-free. This past month, the site had over 1 million visits, and last week it exceeded 90,000 visits per day, so its popularity just continues to grow thanks to your support!

If you would like to purchase a site license for the 2024-2025 school year for just US$70, you can do so right now in one of the following ways:

• credit card through Square (the most popular option)
• school purchase order (contact me for a sales quote – I’m also happy to fill out any paperwork required by your institution or state)
• personal check
• CashApp, PayPal, Venmo or Zelle at chris@chemquiz.net

Additional schools in the same district can purchase an add-on license for 50% off at just US$35 per school. If your school offers physics, you can bundle a site license for the PhysQuiz.net Dashboard for just US$35 more! Please contact me if you have any questions about how to purchase a site license.

Site licenses also help me offer the ChemQuiz.net Dashboard for free to 160 public schools in the United States where the majority of students are economically disadvantaged. If you teach in a high poverty public school (at least 50% of your students on free/reduced lunch or designated “economically disadvantaged”), please send me a link to the supporting documentation and you’ll get a free site license for the ChemQuiz.net Dashboard forever (PhysQuiz.net, too!).

Bug fixes & other improvements

Thanks again to everyone who has reached out with a bug report! Here are all of the updates I’ve made over the past month:

Dashboard – these features and bug fixes also apply to PhysQuiz.net!

• new feature: can now manually order assignments for student Dashboard (thanks, Don!)
• new feature: export results in a grid format similar to the Grades page (thanks, Jason!)
• new feature: option to add links to helpful resources at LibreTexts to the top of assignments
• improvement: can now see score percentage on Results and Grades pages by hovering over a score (thanks, Jana!)
• improvement: created new “Settings” menu and added “User Settings”, “Dashboard Settings” and “School Info” submenus
• bug fix: students with deactivated accounts from last school year could not use a join code to re-register for a new class (thanks, Chris!)
• bug fix: couldn’t change an existing assignment to Continuous mode if it already had a certain number of items (thanks, Pamela!)
• bug fix: the number of questions on an assignment would reset to 10 if there was an error on the assignment creation form (thanks again, Pamela!)
• bug fix: adding filter menus broke the bulk actions menu on the Assignments page
• bug fix: not selecting “export highest score” would generate an error message at the top of the csv file
• bug fix: students without first or last names would cause errors when exporting results as a csv

Exams

• bug fix: tab switches were not being recorded correctly for exams (thanks, Darlene!)

All Quizzes

• bug fix: sig figs in negative numbers were not being counted incorrectly (thanks, Lance!)

Electron Configuration Quiz

• correction: electron configuration for palladium(II) ion (Pd^2+) was being displayed for lead(II) ion (Pb^2+) symbol (thanks, Susan!)

Scientific Notation Quiz

• new feature: added explanations (solutions) for all problems

SI Conversions Quiz

• improvement: better number formatting

Significant Figures Quiz

• new feature: added problems to round numbers to a certain number of sig figs
• new feature: added option to choose thousands separator for numbers (commas, spaces or none)
• bug fix: student answers entered as words instead of numbers (e.g., entering “two” instead of “2”) were crashing the quiz (thanks, Lan!)

Other improvements

• new feature: Quick Start Guide for new teacher accounts on Documentation page

Thanks again to everyone who has sent in a suggestion or bug report, and please keep sending them in! I do my best to fix bugs as quickly as possible, and I want to keep adding new features (to the best of my coding ability) to make the site more useful and easier to use for everyone.

Help me share ChemQuiz.net with the world!

If you like using ChemQuiz.net, there are three quick and easy things that you can do to help me promote the site!

• Add your school to the list of supporters on the About page! Simply go to the ChemQuiz.net Dashboard, click on “Your Info” in the top menu bar, activate the box next to “Display School on ChemQuiz.net“, and click the “Update Your Info” button.
• Tell another Chemistry teacher about ChemQuiz.net and encourage them to try out the Dashboard!
• Follow @ChemQuizDotNet on Facebook and Threads and share my updates with your fellow Chemistry teachers!

For those of you in the United States, I hope the school year has started well for you and that you were able to enjoy this three-day weekend. After all, we have weekends in part because of massive strikes by labor unions in the late 1800s and early 1900s, so I hope that’s something we can all appreciate on this Labor Day.

Thanks again to everyone for all of your support, suggestions and feedback as we start up ChemQuiz.net‘s fifth school year! Please get in touch with me any time via the Contact form or email me at chris@chemquiz.net if you have any questions, comments, or concerns. Take care, stay safe, and make sure you get your updated covid and flu shots so you can stay healthy this school year!

-Chris

Hi everybody! I hope you’ve all been doing well over the past three months. In this newsletter, I’ve included the following important updates about ChemQuiz.net:

• *NEW* Continuous questions mode for all quizzes!
• Lots of other *NEW* features – dark mode, assignment tags, sig fig explanations
• Site licenses for 2024-2025 school year
• Bug fixes and other improvements

There’s a lot to cover and I know many of you are already starting a new school year, so I’ll get right to it!

*NEW* Continuous questions mode!

I’ve added a new “Continuous” mode that will generate unlimited questions for your students, one at a time, and provide immediate feedback after each question. The Dashboard will keep track of their total score and append each question and response to their results so you can review them. Here’s an example from the Significant Figures Quiz that also demonstrates the new “Dark mode” feature:

One benefit of Continuous mode is that you can set a threshold on the assignment so that students will still have to answer enough questions correctly in order to complete the assignment but they get as many tries as they need in order to do it. I’m hoping that this decreases student anxiety and gives them more encouragement to try without worrying about getting questions wrong (shout-out to my fellow Phil Schlechty fans – you know who you are!) I plan on using this new feature in my own classes this upcoming school year for in-class practice and formative assessment.

Continuous mode can be activated on any assignment by selecting it under “Number of items” when you create or edit an assignment in the ChemQuiz.net Dashboard:

It’s also available on all quizzes on PhysQuiz.net! I’ve activated Continuous mode on the Significant Figures Quiz for everyone who wants to try it out. Please note that Continuous mode disables a few assignment features such as limiting attempts and saving progress (since it already saves each question), and it’s not available for exams. Let me know what you think of the new feature, and thanks to Jason, Don and Malcolm for the suggestions and inspiration!

Lots of other *NEW* features!

I’ve also added a number of other new features to ChemQuiz.net that I hope you and your students will like! Here’s a quick rundown:

• dark mode† available on all quizzes and the Dashboard (see above)
• explanations for sig fig problems† (also see above)
• assignment tags*† for better organization (see below)

• view saved student progress*† on an assignment in the Dashboard before it’s submitted (see below)

• new layout for Types of Matter Quiz justification questions (see below)

• include and exclude specific items* on the Laboratory Equipment Quiz in the Dashboard
  

FYI new features that are marked with an asterisk (*) are only available to schools with an active ChemQuiz.net Dashboard site license; new features that are marked with a dagger (†) are also available on PhysQuiz.net.

Site licenses for the 2024-2025 school year

Speaking of site licenses – thank you to everyone who has purchased or renewed their school’s site license for the ChemQuiz.net Dashboard for the 2024-2025 school year! Site licenses help me pay for the web hosting and software I use to write the quizzes, and it keeps the website ad-free. This past school year, ChemQuiz.net averaged about 1 million visits per month, and 18,396 students from 210 schools in six countries completed 372,177 assignments on the ChemQuiz.net Dashboard. The site’s popularity has grown beyond my wildest expectations!

If you would like to purchase a site license for the 2024-2025 school year for just US$70, you can do so right now in one of the following ways:

• credit card through Square (the most popular option)
• school purchase order (contact me for a sales quote – I’m also happy to fill out any paperwork required by your institution or state, and I’m now an officially registered business in New Jersey, too! 😂)
• personal check
• CashApp, PayPal, Venmo or Zelle at chris@chemquiz.net

Additional schools in the same district can purchase an add-on license for 50% off at just US$35 per school. If your school offers physics, you can bundle a site license for the PhysQuiz.net Dashboard for just US$35 more! Please contact me if you have any questions about how to purchase a site license.

Site licenses also help me offer the ChemQuiz.net Dashboard for free to 150 public schools in the United States with high rates of poverty. If you teach in a high poverty public school or school district (at least 50% of your students on free/reduced lunch or designated “economically disadvantaged”), please send me a link to the supporting documentation and you’ll get a free site license for the ChemQuiz.net Dashboard forever (PhysQuiz.net, too!).

Bug fixes & other improvements

Besides Continuous mode, the biggest update this summer was invisible, because I spent a LOT of time preparing the site for a major upgrade of PHP, the web server software that powers everything on ChemQuiz.net! This should make the website run faster and more securely. Unfortunately, the upgrade broke some quizzes and a few Dashboard features when I performed the upgrade in early July, but I’ve tracked down a lot of them thanks to teachers who were using the site over the summer and reached out when something wasn’t working properly.

Here are all of the updates I’ve made since the last newsletter I sent back in May:

Everywhere

• new feature: “Dark mode” (thanks to my son for the suggestion!)

Dashboard – these features and bug fixes also apply to PhysQuiz.net!

• new feature: added class and tag filter menus to improve assignment organization (thanks, Matthew!)
• improvement: can now view student progress on an assignment even though it hasn’t been turned in yet (thanks, Vilma & Danielle!)
• bug fix: teachers could create student accounts that weren’t email addresses through CSV roster import (thanks, Stephanie!)
• bug fix: CSV results export wasn’t working after PHP upgrade (thanks, Corey!)
• bug fix: displaying student deletion confirmation form would cause Dashboard to crash due to incorrectly formatted count() function (thanks, Jason!)
• bug fix: “Time to Complete” in student result details was off by 5 hours (thanks, Nick!)
• bug fix: most recent results were not showing up due to a miscalculation in the number of Results pages
• bug fix: student usernames would not show up across the Dashboard if student did not have a first & last name saved in the Dashboard

All Quizzes

• improvement: Presentation mode is now available to everyone on all quizzes
• improvement: custom assignment names are now displayed in web browser tab title
• bug fix: decimal values with multiple zeros after the decimal point sometimes had the distance from the decimal calculated incorrectly

Acid-Base Neutralization Quiz

• bug fix: disabled multiprotic weak acids in weak acid-strong base problems (thanks, Scott!)

Average Atomic Mass Quiz

• bug fix: multiple choice distractors were not very random

Concentrations & Colligative Properties of Solutions Quiz

• bug fix: van ‘t Hoff factor was being excluded from vapor pressure lowering problems (thanks, Mary Ann!)
• bug fix: weak acids were being included in problems where the number of ions produced in solution mattered (thanks again, Mary Ann!)
• bug fix: correct answers weren’t being rounded correctly, which sometimes affected scoring (thanks, Michele!)
• bug fix: blank word problems were being generated for some freezing point depression problems (thanks, Andrew!)
• bug fix: dilution problems were sometimes being generated with moles as the solution unit (thanks, John!)

Electron Configuration Quiz

• bug fix: short incorrect answers (less than three characters) would crash the quiz

Enthalpy Quiz

• bug fix: monohydrate compounds were crashing the quiz when they were randomly selected for a problem

Kinetics & Rate Laws Quiz

• bug fix: half-life calculations were using the double precision value randomly generated by the quiz for At instead of the value displayed in the problem that was rounded to 3 sig figs, leading to mathematically valid answers being scored as incorrect (thanks, Mary Ann!)

Laboratory Equipment Quiz

• improvement: added an advanced option in the Dashboard to include specific categories of equipment and exclude specific pieces of equipment (thanks, Tonda!)

Molar Conversions Quiz

• bug fix: attempting to load saved student progress crashed the quiz in certain situations if gases were involved (thanks, Matthew!)

Naming Compounds & Calculating Molar Masses Quiz

• improvement: column widths on the quiz page were behaving strangely

Nuclear Reactions Quiz

• bug fix: test code was being displayed when it should have been removed (thanks, Matthew!)
• bug fix: blank answers were being graded using the last values entered by the student instead of being automatically marked wrong

pH & pOH Calculations Quiz

• bug fix: scientific notation formatting for student answers on the results page was not consistent with what they entered

Significant Figures Quiz

• new feature: added explanations (solutions) for counting and arithmetic problems
• improvement: added parentheses around scientific notation values in math problems (thanks, Tony!)

Stoichiometry & Limiting Reagents Quiz

• bug fix: percent yield problems were crashing the quiz due to backward compatibility code that needed to be updated (thanks, Debbie!)

Types of Matter Quiz

• improvement: changed how justification questions are displayed so that the quiz is compatible with the new Continuous mode

Other improvements

• improvement: updated PHP to latest version
• bug fixes: many code updates and improvements necessitated by server software upgrade this summer
• maintenance: archived all assignments, classes, student accounts and results from the 2023-2024 school year

Thanks to everyone who sent in a suggestion or bug report, and please keep submitting your suggestions and bug reports! With the server upgrade and the new features I’ve added, there are bound to be things that don’t work as properly as they should. The sooner I find out about a bug, the sooner I can fix it!

Help me share ChemQuiz.net with the world!

If you like using ChemQuiz.net, there are three quick and easy things that you can do to help me promote the site!

• Add your school to the list of supporters on the About page! Simply go to the ChemQuiz.net Dashboard, click on “Your Info” in the top menu bar, activate the box next to “Display School on ChemQuiz.net“, and click the “Update Your Info” button.
• Tell another Chemistry teacher about ChemQuiz.net and encourage them to try out the Dashboard!
• Follow @ChemQuizDotNet on X (formerly Twitter), Facebook and Threads and share my updates with your fellow Chemistry teachers!

I wanted to thank everyone who completed the end-of-year survey this past Spring! The teachers in the survey gave me a lot of useful feedback on the site, and their suggestions have helped me prioritize what improvements I should focus on for this upcoming school year. On a related note, I was selected as an AP scorer, so I spent a week in June scoring hundreds of AP Computer Science A FRQs, and that mind-numbing experience of trying to interpret handwritten code for eight hours a day honestly helped me a lot with my own coding skills. I’m really excited about all the possibilities for ChemQuiz.net this school year!

In the May newsletter, I wrote about how I was going to take our school’s Environmental Club to the Ohio Envirothon Competition. The “EnviroQueens” ended up earning 3rd place in Oral Presentation and 6th place overall out of 20 teams from across the state! Most importantly, we all had a great time – even the student who got a very, very flat tire on the way down to Nelsonville. It was a wonderful way for these awesome seniors to cap off their high school careers, and I’m going to miss them all as they go off to college in the Fall! 😭

Thanks for letting me brag about my students, and thanks again to everyone for all of your support, suggestions and feedback over the past four years! You’ve all been very kind to me. Please reach out any time via the Contact form or at chris@chemquiz.net if you have any questions, comments, or concerns. Take care, stay safe, and good luck with this school year!

-Chris

Hello again! For everyone who’s almost done with this school year, I hope that it’s wrapping up well for you and your students. In this newsletter, I’ve included the following important updates about ChemQuiz.net:

• *NEW* Solubility rules questions!
• End of the school year survey – win a $50 gift card!
• Site license renewals for 2024-2025 school year
• IMPORTANT annual site maintenance starting July 1st
• Bug fixes and other improvements

*NEW* Solubility rules questions!

The primary goal I had when I created ChemQuiz.net back in 2020 was to provide a useful and accurate resource for Chemistry teachers and students. As the site has grown and become more popular, I’ve tried to fill in some of the gaps that exist in the quiz topics, which can sometimes be a real challenge, depending on the topic.

I just added a topic that was long overdue – solubility rules! In the Solubility Quiz, you can now have students predict whether an ionic compound will be soluble, slightly soluble, or insoluble in water under standard conditions. Just select the new option, “Determine solubility of a compound in water” when generating a quiz or creating an assignment:

This option will generate multiple choice questions like this:

The Solubility Quiz pulls from 400 different ionic compounds in the database to generate these problems, so there should be plenty of practice for your students. Thanks to Seth, Auburn and Andrew for suggesting this feature!

One of the more frustrating things about creating quizzes that generate random questions about chemistry is that there’s often disagreement between different resources. With respect to solubility, I’ve found that some lists say that lead(II) halides are insoluble, while others say that they’re slightly soluble. I tend to go with the values on Wikipedia since I know there are lots of amazing chemistry nerds out there who make sure those pages are as accurate as possible, but I thought this would be a great opportunity to try out a poll! What do you think – are lead(II) halides (e.g. PbF₂, PbCl₂, etc.) insoluble or slightly soluble?

(PLEASE NOTE: The poll is only available on the email version of the newsletter.)

Let me know what you think! I want the site to be as useful as possible to you and your students, so I appreciate your feedback.

Complete a survey, enter to win a $50 gift card!

For the past three years, I’ve asked every teacher that uses or has signed up for the ChemQuiz.net Dashboard to complete a short survey about how they use the site and what new features they want me to work on. The feedback has been really helpful!

Every teacher who fills out the survey will be entered into a drawing for a $50 Amazon gift card! Only one entry per person, please. The drawing will be on June 15th, so don’t delay! You can fill out the survey here.

Most site license renewals due July 1st

Thank you to everyone who has already renewed their school’s site license for the ChemQuiz.net Dashboard for the 2024-2025 school year! Site licenses are how I pay for the web hosting and the software I use to write the quizzes, and it keeps the website ad-free. I’ve sent out invoices for next school year to everyone with a current site license, but if you didn’t receive one, please let me know.

You can check your school’s site license status by going to the ChemQuiz.net Dashboard and clicking on “School Info” in the top menu.

Once your site license for the ChemQuiz.net Dashboard expires, you won’t be able to create new student accounts, classes or assignments. If you plan on renewing for next school year but you need a little extra time for the paperwork to go through, just drop me a line and I’ll extend your school’s expiration date. I’ve taught in three public school districts over my career and each handled purchase orders differently, so I understand how complicated the process can be.

If you currently have a demo account and would like to purchase a site license for the 2024-2025 school year for just US$70, you can do so right now in one of the following ways:

• credit card through Square (the most popular option)
• school purchase order (contact me for a sales quote – I’m also happy to fill out any paperwork required by your institution or state)
• personal check
• CashApp, PayPal, Venmo or Zelle at chris@chemquiz.net

Additional schools in the same district can purchase an add-on license for 50% off at just US$35 per school. If you also teach physics or you have a colleague who does, you can bundle a site license for the PhysQuiz.net Dashboard for just US$35 more! Please contact me if you have any questions about how to purchase a site license.

Site licenses also help me offer the ChemQuiz.net Dashboard for free to 143 public schools in the U.S. with high rates of poverty. If you teach in a high poverty public school or school district (at least 50% of your students on free/reduced lunch or designated “economically disadvantaged”), please send me a link to the supporting documentation and you’ll get a free site license for the ChemQuiz.net Dashboard forever.

Important annual site maintenance

Over the past four years, ChemQuiz.net has added more schools with more students who generate more quiz results, so every summer I have to archive older material to keep the site running efficiently. For example, there are currently over 355,000 quiz results from this school year in the database so far, which is a 152% increase over last school year’s total! 😱

I’m going to be performing the following maintenance items over the summer, starting on or shortly after July 1st:

• All students accounts, assignments, quiz results, and classes created during the 2023-2024 school year (7/1/23 – 6/30/24) will be archived (but not deleted)
• All student accounts created during the 2022-2023 school year will be deleted

Items that are archived will still be accessible to you through the ChemQuiz.net Dashboard. If you don’t want me to archive your stuff, or if you operate on a different school calendar, please let me know before July 1st! Also, I perform regular backups of all data on the site, so I can always restore anything you might need.

Bug fixes & other improvements

Thanks to all of the teachers and students who send in bug reports and suggestions for improving ChemQuiz.net! Here are all of the updates I’ve made since the last newsletter:

Dashboard – these features and bug fixes also apply to PhysQuiz.net!

• improvement: added link to renew site license on “Your School” page
• improvement: added an alert about “require login” and “save progress” options (thanks, Nate!)
• improvement: changed Dashboard page titles in web browsers for more accurate bookmarking
• bug fix: trying to create an exam led to a “Column ‘quizID’ cannot be null” error (thanks, John, Matthew and Nick!)
• bug fix: using the bulk actions menu without selecting assignments first gave a MySQL error (thanks, Yvonne!)

Balancing, Identifying & Predicting Chemical Equations Quiz

• correction: FeCl2 + O2 -> Fe2O3 + Cl2 was balanced incorrectly (thanks, David!)

Chemical Equilibrium Quiz

• bug fix: removed several divide by zero errors that were causing the quiz to crash in PHP8

Chemical Thermodynamics Quiz – (thanks to Mary Ann for all of these!)

• bug fix: ∆S word problems involving grams were using moles value instead of mass value
• bug fix: ∆S problems were mixing up ∆H with q
• bug fix: ∆S problems had incorrect units in some solution setups

Concentrations & Colligative Properties of Solutions Quiz

• bug fix: units were missing in dilution problems (thanks, Maggie!)
• bug fix: given values were being rounded too much in certain situations (thanks again, Maggie!)
• bug fix: correct answers weren’t being rounded correctly, which sometimes affected scoring (thanks, Michele!)
• bug fix: blank word problems were being generated for some freezing point depression problems (thanks, Andrew!)
• bug fix: dilution problems were sometimes being generated with moles as the solution unit (thanks, John!)

Enthalpy Quiz

• bug fix: formulas for hydrates were showing up with incorrect formatting

Naming Compounds & Calculating Molar Masses Quiz

• improvement: added 105 new compounds (beryllium, caesium, cadmium, gallium, gold(III), nickel(II), rubidium, vanadium(III), thiocyanate) to the database
• bug fix: blank multiple choice options were sometimes being generated

Nuclear Reactions Quiz

• bug fix: reactions with double beta decay mode would cause the quiz to crash when generating multiple choice options

Organic Nomenclature Quiz

• bug fix: carboxylic acids weren’t being displayed in quiz when they were the only compound class selected (thanks, Matthew!)
• bug fix: carboxylic acids weren’t being scored correctly (thanks again, Matthew!)

pH & pOH Calculations Quiz

• bug fix: small numbers (e.g., 1e-14) were not being formatted properly for scientific notation (thanks, Tony!)

Redox Reactions & Net Ionic Equations Quiz

• bug fix: coefficient for hydrogen ions in redox reaction between iodate ion and hydrogen sulfite ion was incorrect (thanks, Lan!)

Solubility Quiz

• new feature: classify ionic salts as soluble or insoluble in water using solubility rules (thanks Seth, Auburn and Andrew!)

Stoichiometry & Limiting Reagents Quiz

• bug fix: quiz was some correct answers as incorrect when they were in scientific notation (thanks, Karen!)

Thermochemical Equations Quiz

• bug fix: clicking the “Load More Problems Like This” button would cause the quiz to crash 🤦🏻‍♂️

Other improvements

• maintenance: made lots of “under the hood” code improvements to the quizzes to prepare for server software upgrade this summer

Please keep submitting your bug reports and suggestions! It makes it much easier to fix things when people tell me about them, and ChemQuiz.net has improved a lot over the past four years because of all the teachers and students who have reached out to help.

Help me share ChemQuiz.net with the world!

If you like using ChemQuiz.net, there are three quick and easy things that you can do to help me promote the site!

• Add your school to the list of supporters on the About page! Simply go to the ChemQuiz.net Dashboard, click on “Your Info” in the top menu bar, activate the box next to “Display School on ChemQuiz.net“, and click the “Update Your Info” button.
• Tell another Chemistry teacher about ChemQuiz.net and encourage them to try out the Dashboard!
• Follow @ChemQuizDotNet on X (formerly Twitter), Facebook and Threads and share my updates with your fellow Chemistry teachers!

We only have two more weeks until semester exams at my school, and then I get to take our Environmental Club to the Ohio Envirothon Competition for the fourth year in a row! This year’s state competition takes place in June at Hocking College in Nelsonville, Ohio, which is in the southeast corner of the state and has some of the prettiest landscape around. I know I mentioned this last spring, but if you’re in the U.S. or Canada and your state or province participates in the Envirothon competition, I highly recommend getting involved!

Thanks again for all of your support, suggestions and feedback over the past four years! Working on ChemQuiz.net with so many great science teachers from all over the world has been an awesome and uplifting experience. Please feel free to reach out any time via the Contact form or at chris@chemquiz.net if you have any questions, comments, or concerns. Take care, stay safe, and for those of you in the United States and Canada, good luck with the rest of this school year!

-Chris

Hi everybody, I hope you’re doing well! In this newsletter, I’ve included the following important updates about ChemQuiz.net:

• *NEW* Concentration and colligative properties problems!
• *NEW* One-at-a-time question mode!
• *NEW* Exclude specific ions from the Naming Compounds Quiz!
• Bug fixes and other improvements
• Site license renewals for 2024-2025 school year

*NEW* One-at-a-time question mode!

Back in December, I received a great suggestion from Malcolm to create a new quiz mode that would only show one question at a time based on feedback he was getting from his students who felt stressed when they saw all of the questions at once. I’ve been teaching for 26 years and have also noticed an increase in anxiety triggers in my own students, so I figured out how to add a new “One question at a time” mode to all of the quizzes on the site!

When you’re creating an assignment, choose this option at the bottom of the form:

Then, when students take the quiz, the questions will look something like this:

The “Grade It!” button only appears on the last question to prevent students from clicking it too early (thanks, Matthew!), but if you activate the “Save progress” option, that button will still show up on every question (thanks, Yvonne!).

Currently, this option is only available to teachers and students at schools with active site licenses. Thanks again to all of the teachers who helped me figure out how to make this new feature happen! I’m hoping that it helps students focus on the problem in front of them instead of worrying about how many they still have left to complete.

*NEW* Concentration & colligative properties problems!

Last month, I started filling in some topical gaps in ChemQuiz.net by adding molecular Lewis structures to the Lewis Dot Structures Quiz. This month, I’ve added colligative properties problems to the renamed Concentrations & Colligative Properties of Solutions Quiz – vapor-pressure lowering (Raoult’s Law), boiling-point elevation and freezing-point depression!

I also added mass percentage, molality, mole fraction (X) and parts per million concentration calculations to the quiz:

To minimize student confusion, I also added an option to lock solvent & solution units to appropriate values based on the problem type:

For example, if you select this option and you’re generating molality problems, all of the solvent values will be in kilograms. Otherwise, the quiz will choose randomly from the solvent units you’ve chosen.

I did my best to test out all of the new problem types, including as multiple choice questions, but if you come across any impossible concentrations, weird bugs or other issues, please let me know. I hope the new colligative property problems and concentration options are useful for you and your students. Thanks to Ken, Andrew, Kelly, Barbara, Abby, Helen, Theresa and all of the teachers who reached out with suggestions on how to improve this quiz!

*NEW* Exclude specific ions!

In last month’s newsletter, I wrote about adding polyatomic ions questions to the Naming Compounds & Calculating Molar Masses Quiz. Shortly after sending that out, I received a fantastic rant from original ChemQuiz.net supporter Ryan about how much he hates mercury ions! 😂 His email made me laugh so hard that I realized I just had to do something about the numerous requests I’ve received over the years to allow teachers to exclude certain ions from that quiz.

My main concern about adding this feature to the quiz was due to the number of options that it already has. The Naming Compounds & Calculating Molar Masses Quiz is by far the most popular quiz on the site, so I didn’t want to add even more options that might confuse users.

To square this circle, I created a new “advanced option” category that only appears for teachers in the ChemQuiz.net Dashboard! Teachers at schools with an active site license can now exclude specific ions from the Naming Compounds & Calculating Molar Masses Quiz by creating a new assignment or editing an existing assignment and checking the boxes next to ions they don’t want to show up for their students:

Thanks also to Bryan, Caytee, Drew, Matthew and all of the other teachers over the years who suggested this feature! I know you’ve been waiting for this for a while, so I appreciate your patience while I figure out (what I hope is) the best way to implement it. Ideas like these have helped me improve ChemQuiz.net over the past four years, so please keep sending them in!

Bug fixes & other improvements

As always, thanks so much to all of the teachers and students who send in bug reports and suggestions for improving ChemQuiz.net! As much as I want the site to be bug-free, there’s so much code that it’s simply impossible – for example, the Dashboard alone has over 10,000 lines of code in three different programming languages. 😱 That’s the reason I keep track of every bug or idea that I receive, because I couldn’t make these improvements without your help and I want to acknowledge everyone’s support. Here are all the updates I’ve made since the last newsletter:

Dashboard – these features and bug fixes also apply to PhysQuiz.net!

• improvement: allow teachers to limit the number of attempts to a specific number (e.g., 3) instead of just “yes” or “no” (thanks, Yana!)
• improvement: export results CSV in format for Canvas (thanks, John, Matthew and Malcolm!)
• bug fix: user accounts created with malformed usernames couldn’t see the Dashboard (thanks, Stephanie!)

Exams

• improvement: updated exam page language for inactive exams
• bug fix: “Save Progress” button was displaying in exams even when the setting was off (thanks, Yvonne!)

All Quizzes

• new feature: option for students to see one question at a time (thanks, Malcolm!)
• improvement: students were accidentally hitting the “Grade It!” button when they meant to go on to the next question in “one at a time” mode, so the button was moved to the last question (thanks, Matthew!)
• bug fix: word wrap was not working in “one at a time” mode (thanks again, Matthew!)
• bug fix: “Save Progress” button was not displaying in “one at a time” mode (thanks, Yvonne!)

Acid-Base Equilibrium Quiz

• bug fix: key was not displaying in printable mode

Balancing, Identifying & Predicting Chemical Equations Quiz

• improvement: FeCl2 + O2 reaction produces Fe3O4, which is confusing to students, so I removed it from the quiz (thanks, Yvonne!)

Chemical Thermodynamics Quiz

• bug fix: incorrect values and units for free-energy change were showing up for word problems when solving for standard entropy change (thanks, Rhonda!)

Concentrations & Colligative Properties of Solutions Quiz

• new feature: added ppm problems (thanks Barbara, Abby, Kelly, Helen and Susan!)
• new feature: added % mass problems (thanks, Kelly and Andrew!)
• new feature: added Raoult’s Law and colligative properties problems (thanks, Ken and Andrew!)
• bug fix: check values for solute and concentration to make sure they’re realistic (thanks, Theresa!)

Lewis Dot Structures Quiz

• correction: Lewis structure for propyne had too many hydrogens (thanks, Timothy!)
• correction: lewis structure for GaH3 was incorrect (thanks, Scott!)
• bug fix: quiz was not grading multiple choice responses for “draw structure” questions (thanks again, Scott!)
• bug fix: duplicate Group number options were showing up for multiple choice questions (thanks, Danielle!)

Molecular Geometry & VSEPR Quiz

• polyatomic ions were showing up as polar molecules even if they’re not technically polar (thanks, Chad!)

Naming Compounds & Calculating Molar Masses Quiz

• new feature: allow teachers to exclude specific ions (thanks, Bryan and Ryan!)
• improvement: added CH3CO2 and CH3COO as alternative responses in all acetate compounds (thanks, Katharine!)
• correction: dichromate ion charge was incorrect (thanks, Yvonne!)
• correction: peroxide ion formula was incorrect (thanks, Brenda!)
• bug fix: blank answers were being marked as correct for compounds with alternate formulas in the database (thanks, Caytee!)
• bug fix: nitrite was missing from the list of polyatomic ions to exclude (thanks again, Caytee!)
• bug fix: when students forget to capitalize elements in polyatomic ion, like Nh instead of NH, it marks it wrong but tells them they forgot to capitalize the “L” (thanks again, Caytee!)
• bug fix: new “exclude ions” feature was preventing quiz from selecting molecular compounds (thanks, Ryan!)
• bug fix: IUPAC spellings of “aluminium” and “caesium” were not always accepted as correct answers in compound names (thanks, Danielle!)

Periodic Trends Quiz

• new feature: added “Additional elements to include” option for Z > 86 (thanks, Mary Ann!)
• correction: ionic radius for hydrogen was for anion instead of cation (thanks, Scott!)

Stoichiometry & Limiting Reagents Quiz

• new feature: changed “percent yield” option so that it’s a distinct problem option instead of randomly showing up in problems (thanks, Matthew!)
• improvement: distractors for percent yield multiple choice problems were often over 100% (thanks again, Matthew!)
• bug fix: phase change “reactions” from Hess’s Law Quiz were included in problem sets, resulting in strange behavior, so they’re now excluded from problems (thanks again, Matthew!)

Other improvements

• bug fix: creating users through CSV import wasn’t working due to a backend conflict with WooCommerce and an older version of PHP (thanks, Corey!)

Please keep submitting your bug reports and suggestions! ChemQuiz.net has improved significantly over the past four years because of all the teachers and students who have reached out to me, so thank you all again for your support.

Site license renewals for 2024-2025 school year

It’s renewal time! In the next few weeks, I’m going to start sending out invoices for ChemQuiz.net Dashboard site licenses for the 2024-2025 school year. Like last year, I’ll generate invoices using your most recent payment method; for example, if you purchased a site license with Square, you’ll get an invoice through Square. If you purchased a site license through a school purchase order, I’ll email you an invoice directly as a PDF attachment.

Site licenses are how I pay for web hosting and site security as well as the software I use to write and maintain the quizzes, and it keeps the website ad-free. I understand that financial situations can change from year to year, so if you’ve decided not to renew your ChemQuiz.net Dashboard site license for next school year, just let me know and I’ll make sure you don’t receive an invoice or any reminders. I don’t want to bother any of my fellow educators.

If you’d like to purchase a 12-month ChemQuiz.net site license or renew your existing license, you can do so right now in one of the following ways:

• • credit card through Square (the most popular option)
  • school purchase order (contact me for a sales quote – I’m also happy to fill out any paperwork required by your institution or state)

• personal check
• CashApp, PayPal, Venmo or Zelle at chris@chemquiz.net

Additional schools in the same district can purchase an add-on license for 50% off at just US$35 per school. If you also teach physics or you have a colleague who does, you can bundle a site license for the PhysQuiz.net Dashboard for just US$35 more! Please contact me if you have any questions about how to purchase a site license.

Finally, if you teach in a high poverty public school or district (at least 50% of your students on free/reduced lunch or designated “economically disadvantaged”), please send me a link to the supporting documentation and you’ll get a free site license for the ChemQuiz.net Dashboard forever (PhysQuiz.net, too!). I want ChemQuiz.net to be a useful resource for as many students as possible.

Help me share ChemQuiz.net with the world!

If you like using ChemQuiz.net, there are three quick and easy things that you can do to help me promote the site!

• Add your school to the list of supporters on the About page! Simply go to the ChemQuiz.net Dashboard, click on “Your Info” in the top menu bar, activate the box next to “Display School on ChemQuiz.net“, and click the “Update Your Info” button.
• Tell another Chemistry teacher about ChemQuiz.net and encourage them to try out the Dashboard!
• Follow @ChemQuizDotNet on X (formerly Twitter), Facebook and Threads and share my updates with your fellow Chemistry teachers!

We just finished our Spring Break in my school district 😭, so while I’m sad that it’s over, that means we have less than eight weeks until the end of the school year! I hope your school year is wrapping up well, and if you have to deal with state-mandated testing like we do in Ohio, I hope it all passes as quickly and painlessly for you and your students as possible.

Thank you again for your continued support of ChemQuiz.net! Please feel free to reach out to me via the Contact form or at chris@chemquiz.net if you have any questions, suggestions or concerns. Take care, and good luck with the rest of this school year!

-Chris

Hello again, I hope you’ve been doing well! In this newsletter, I’ve included the following important updates about ChemQuiz.net:

• *NEW* Molecular Lewis structures!
• *NEW* Polyatomic ion naming & formula writing!
• Bug fixes and other improvements

*NEW* Molecular Lewis structures!

Now that ChemQuiz.net has been around for almost four years, I feel like I’ve been able to add many of the fundamental quiz and Dashboard features that would be most useful to a high school or introductory college Chemistry course. However, there are still a number of topics that I want to add to the site, and molecular Lewis structures have been at the top of that list for a while now.

After I finished adding multiple choice options to all of the quizzes back in January, I’ve spent the last several weeks collecting and verifying 227 molecular Lewis structures so I could add them to the Lewis Dot Structures Quiz! Here’s an example of one type of question generated by the quiz:I also added the ability to select molecules that either follow the octet rule or don’t follow it (or both!). Here’s an example of a more challenging question about an octet rule-breaker:

I did my best to avoid resonance structures (for now) and I tested out all of the questions, but if you come across any incorrect structures, bugs or other issues, please let me know. I hope the new molecular Lewis structures are useful for you and your students!

*NEW* Polyatomic ion naming & formula writing

Another popular feature request has been to ask me to add a quiz to help students memorize polyatomic ions, but I never felt that topic was significant enough to justify its own separate quiz. However, I recently realized that I had already entered most of the widely known polyatomic ions in the database for a different quiz, so I added them to the Naming Compounds & Calculating Molar Masses Quiz! Here’s an example of the kinds of questions you can now generate:

There are a total of 37 polyatomic ions available, and the quiz should also accept common (non-IUPAC) names as correct (e.g. “bicarbonate ion” will work just as well as “hydrogen carbonate ion”). You can also generate problems for calculating their molar masses.

Thanks to Michelle, Seth & Auburn for giving me this idea! Suggestions like theirs have helped me significantly improve ChemQuiz.net since it first launched in 2020, so please keep sending in your feedback and ideas!

Bug fixes & other improvements

As I’ve said in previous newsletters, I keep track of all the suggestions and bug reports that are sent in, and I try to prioritize bug fixes over adding new features, but sometimes it takes me a while to figure out what’s causing a problem or even how to reproduce it so I can track it down. A few of the bugs listed below were very challenging to resolve, so I just wanted to make sure everyone knew how much I appreciate their help and patience! Here’s a list of all the updates since the last newsletter:

Dashboard – these features and bug fixes also apply to PhysQuiz.net

• new feature: added an expiring progress alert for students at the top of the Dashboard
• bug fix: assignments for “All Classes” weren’t showing up on the Assignments page for colleagues (thanks, Bill!)
• bug fix: overriding a student answer that was marked as “incorrect” would sometimes count for multiple points (thanks, Jason!)
• bug fix: PHP notices were showing up in the production version of the Dashboard (thanks again, Jason!)

Exams

• bug fix: an exam section would be inaccessible to students if they previously completed the assignment that section was based on and “Allow multiple attempts” was turned off (thanks, Cynthia!)

All Quizzes

• improvement: tweaked the design of answer pages on all quizzes so they have similar column widths
• bug fix: students were sometimes being prompted to finish an assignment for “All Classes” that was from a different teacher at their school (thanks, Lauren and Maggie!)

Acid-Base Equilibrium Quiz

• bug fix: the correct answer for [H+] problems was incorrectly calculated as 1.00 for multiple choice questions, resulting in no correct options (thanks, Susan!)
• bug fix: sometimes the correct multiple choice option for the dissociation constant value was marked as incorrect due to rounding

Balancing, Identifying & Predicting Chemical Equations Quiz

• bug fix: diatomic gases were being truncated in multiple choice options for prediction questions (thanks, Matthew!)

Chemical Equilibrium Quiz

• new feature: added “Avoid converting between Kc and Kc when calculating equilibrium constants” option (thanks, Lan!)
• bug fix: solution setups for problems requiring conversion between Kp and Kc were missing some steps (thanks again, Lan!)

Kinetics & Rate Laws Quiz

• bug fix: incorrect values were being used in solution setups for rate law problems with data tables (thanks, Mary Ann!)

Lewis Dot Structures Quiz

• new feature: added Lewis structures for 227 molecules and polyatomic ions (thanks, Mike and Mags!)

Naming Compounds & Calculating Molar Masses Quiz

• new feature: added an option to select polyatomic ions (thanks, Michelle, Seth & Auburn!)
• bug fix: choosing ionic compounds with common polyatomic ions excluded fixed-charge nonmetals like chlorine (thanks, Drew!)
• bug fix: answers for alternate names without a space between the positive ion and parentheses were erroneously being marked as incorrect

Other improvements

• improvement: tweaked site security settings so that a school is less likely to be accidentally blocked by the firewall (thanks, Debbie!)

Please keep submitting your bug reports and suggestions! ChemQuiz.net has improved significantly over the past three and a half years thanks to all the teachers and students who have gotten in touch with me, so thank you all again for your support.

Site licenses for the ChemQuiz.net Dashboard

Site licenses for the ChemQuiz.net Dashboard allow teachers to create assignments for their students and track their progress. Thanks to the many schools, colleges, universities and tutors who have renewed or purchased a site license for this school year! Site licenses are how I pay for web hosting and site security as well as the software I use to write and maintain the quizzes, and it keeps the website ad-free.

If you’d like to purchase a 12-month ChemQuiz.net site license or renew your existing license, you can pay in one of the following ways:

• • credit card through Square (the most popular option)
  • school purchase order (contact me for a sales quote – I’m also happy to fill out any paperwork required by your institution or state, and I’ve already completed student privacy paperwork for states such as CA, IL, WI, and the six state MA-ME-NH-NY-RI-VT Student Data Privacy Consortium)

• personal check
• CashApp, PayPal, Venmo or Zelle at chris@chemquiz.net

Additional schools in the same district can purchase an add-on license for 50% off at just US$35 per school. If you also teach physics or you have a colleague who does, you can bundle a site license for the PhysQuiz.net Dashboard for just US$35 more! Please contact me if you have any questions about how to purchase a site license.

Finally, if you teach in a high poverty public school or district (at least 50% of your students on free/reduced lunch or designated “economically disadvantaged”), please send me a link to the supporting documentation and you’ll get a free site license for the ChemQuiz.net Dashboard forever (PhysQuiz.net, too!). I want ChemQuiz.net to continue to be a useful resource for as many students as possible.

Help me share ChemQuiz.net with the world!

If you like using ChemQuiz.net, there are three quick and easy things that you can do to help me promote the site!

• Add your school to the list of supporters on the About page! Simply go to the ChemQuiz.net Dashboard, click on “Your Info” in the top menu bar, activate the box next to “Display School on ChemQuiz.net“, and click the “Update Your Info” button.
• Tell another Chemistry teacher about ChemQuiz.net and encourage them to try out the Dashboard!
• Follow @ChemQuizDotNet on X (formerly Twitter), Facebook and Threads and share my updates with your fellow Chemistry teachers!

I’m not sure how many of you are in the path of the Great American Eclipse next month on April 8th, but it’s passing through my town (Kent, Ohio) and I’m super excited about it! When the partial solar eclipse happened back in 2017, our district bought eclipse glasses for all of the students and staff, and then we took all the 6-12th graders out to the football stadium to watch it happen (I was also the MC for the event – I wrote a script and everything 😂). Those 6th graders from 2017 are now seniors, so it’s pretty cool that they’ll be able to experience two solar eclipses in such a short span of time!

However, because this will be a total solar eclipse, we’ve been warned by local authorities to start stocking up on food, water, fuel and batteries at least a week before the event because we’re going to be overrun with “eclipse tourists”! Hotels in the area have sold out, school districts in the counties along the path have already canceled for that day, and we’ve been told to expect 6-8 hour delays on roads and highways. 😱 That’s all very concerning, but I’m most worried about the Spring weather in northeast Ohio, which is often overcast and can be very mercurial. I don’t want to have to wait until 2044 to see the next one!

As always, thank you for your continued support of ChemQuiz.net! I hope that the school year has gone well for you so far and that you’re able to take a restful and relaxing break soon. Please feel free to reach out to me via the Contact form or at chris@chemquiz.net if you have any questions, suggestions or concerns. Take care!

-Chris