ChemQuiz.net

Hello again! I hope you’re doing well now that we’re over halfway through the school year. I apologize for sending this month’s newsletter later than I would have liked, but I wanted to get the new Kinetics & Rate Laws Quiz to a point where it was usable and I could share it with you. Unfortunately, that took longer than I expected! It turns out that rate laws are really complicated – who knew? 😂

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Discounted site license

Now only US$30 through July 1, 2023!

If you haven’t purchased a site license for the ChemQuiz.net Dashboard, you’re missing out on the ability to create assignments and keep track of student progress for each of the 35 quizzes available on the site! Even though we’re past the halfway point of the school year, there are still some challenging, two-letter Chemistry exams looming on the horizon (you know which ones I’m talking about).

Because of this, I wanted to offer a 40% discount – only US$30! – through July 1st, which should cover the rest of this school year. In addition to being able to create your own assignments for each quiz based on options that you choose, you also get access to “Presentation mode”, which lets you put quizzes up on your projector or interactive whiteboard so you can work on them together as a class. We did this in my own classes last week to review balancing equations:

You can try out Presentation mode on the Significant Figures Quiz to see if it would be useful for you and your classes.

Site licenses help me pay for web hosting and the software I use to write the quizzes, and I’ve been able to focus more time on writing quizzes by letting go of coaching and other supplementals where I teach. If you’re interested in purchasing a discounted site license, I can accept payment through school purchase order or personal check, or via CashApp, PayPal, Venmo or Zelle at chris@chemquiz.net, or you can pay with a credit card through Square. Please reach out to me if you have any questions at all!

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New Kinetics & Rate Laws Quiz mostly done

Thanks to the help of the numerous teachers who sent me suggestions and resources after the last newsletter, I’ve made significant progress on making a new Kinetics & Rate Laws Quiz! Right now, it can generate problems for reaction rates, rate laws, and the change of concentration over time using generic “A + B → C + D” equations. I’d really appreciate it if you could take a moment to check it out and give me some feedback, especially on the validity of the randomly-generated numbers.

As I mentioned before, I wanted to send out the February newsletter last weekend, but I wanted something functional to share, and I was struggling with getting the quiz to calculate correct answers from the problems. This prevents students from just looking at the HTML source code to try to find the answer, something I figured out early on when I wrote my first practice quizzes for my blog over a decade ago. I wanted to add half-life problems when given data tables, but the randomly generated numbers are still coming out weird. After I fix that, I want to go back and add real chemical equations before I officially publish the quiz.

Thanks again to Susan, Terrie, Matt, Mark and Caytee for your generosity – I greatly appreciate it!

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New quiz features & bug fixes

I hear from teachers and students all the time about suggestions for improving quizzes and about bugs on ChemQuiz.net that I didn’t know about, and it’s great! Since I teach full time, it’s difficult for me to find the time and mental energy to think of improvements and find all the bugs on my own during the school year, so I rely on feedback from everyone who uses the site. Here’s a rundown of the most recent improvements:

Dashboard

• assignments assigned to “All Classes” weren’t showing up for individual classes in the filter on the Grades page (thanks David and Danny!)

All Quizzes

• “silicate” compounds are vague across quizzes so I made them all explicitly “orthosilicate” in the database (thanks, Susan!)
• additional “under the hood” improvements

Acid-Base Equilibrium Quiz

• answers weren’t rounding or displaying the proper units

Balancing, Identifying & Predicting Chemical Equations Quiz

• added an option to use chemical names instead of formulas (thanks, Sylvie and Anamar!)
• added a database setting for some products that are too hard to reliably predict (e.g., CO in combustion reactions) (thanks, David!)
• added tooltip hover boxes for chemical names on the score page

Electron Configuration Quiz

• added an option to limit problems to the first 20 elements (thanks, Jason!)

Molecular Geometry & VSEPR Quiz

• valence electrons weren’t being counted correctly for ions 🤦🏻‍♂️ (thanks, Tony!)

Naming Compounds & Calculating Molar Masses Quiz

• now accepts compound names without a space before the roman numeral (pointed out by my students)

Scientific Notation Quiz

• numbers weren’t being stored properly in hidden input when converting from scientific notation (thanks, Lucas!)

SI Conversions Quiz

• guesses of a large order of magnitude (10^10 or greater) weren’t being handled properly (thanks, Mary Ann!)

Thanks again to everyone who sent in a suggestion or bug report! There are still several that I need to address but I haven’t been able to yet because I’ve been working on the new kinetics quiz, so I appreciate your patience. If you come across anything that isn’t working correctly or you come up with an idea for a new feature or quiz, please let me know by filling out the Contact form or emailing me directly at chris@chemquiz.net!

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Free site licenses for eligible schools

When I first launched ChemQuiz.net in the summer of 2020, I wanted the site to be useful to as many students and teachers as possible. This is the reason the quizzes are all free to use, including all of their options. Since I’ve taught at a high-poverty school, I know how difficult it can be to get the necessary resources for science classes. At my previous school, we used to have our science students do a big fundraiser each fall just so we could buy equipment and supplies!

I also made the decision to give free site licenses for the ChemQuiz.net Dashboard to those schools, and I’ve been really happy with the results so far, so I wanted to share some statistics about the program from this school year:

• 84 high schools across the United States have received free site licenses
• 2,410 students from those schools have active Dashboard accounts
• teachers from those schools have created 295 assignments
• students have completed assignments 20,482 times (as of the evening of Super Bowl Sunday)

These numbers are only possible thanks to the schools and individuals who’ve purchased site licenses, so THANK YOU for your continued support of ChemQuiz.net! My dream is to someday get an email from a student who just completed their undergrad Chemistry degree and used the site back in high school to get better at chemistry – that would be really, really cool!

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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!

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

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Thanks again for your continued support and kind words about ChemQuiz.net! Please feel free to contact me any time if you have any questions or suggestions for improvement, or if you run into any problems while using the site. Good luck with the rest of this school year!

-Chris

Happy New Year, everyone! I hope 2023 has started well for you and your students. I wanted to let you know about a brand new quiz that I just finished as well as some important bug fixes, and I also wanted to ask for help with the next quiz I’d like to write.

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Brand new quiz!

*NEW* Scientific Measurements Quiz – thanks, Fionna!

• make accurate scientific measurements using diagrams of rulers, graduated cylinders and thermometers
• fill-in-the-blank or multiple choice questions

Here are some examples of the diagrams generated by this new quiz:

  

I received a suggestion to write this quiz about two years ago, but I kept putting it off because I didn’t know how to generate dynamic drawings beyond the isotope notation in the Nuclear Reactions Quiz. However, I started working on this quiz a few months ago when I was learning to generate dynamic drawings of particles for the Types of Matter Quiz because I needed measurement diagrams for my own Chemistry students, who haven’t had much hands-on lab experience so far thanks to the pandemic. I’m not sure if you’re seeing this with your students, but even simple tasks like estimating a digit between the lines on a ruler or taking a reading at the bottom of the meniscus have been challenging to mine.

So, I made some ruler and graduated cylinder diagrams that I used in class to try to help them, but I needed winter break to have time to sit down and figure out how to generate those diagrams dynamically and accurately. Once I finished the quiz, I also added alcohol thermometers for fun, if any of you are still using those with your students, but I stopped short at adding triple beam balances (for now!). I know that many of you won’t need this quiz until next fall, but I hope it’s helpful now for those of you who teach on a block schedule or in college and are just starting with your Chemistry students.

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Disabled “Enter” key on all quizzes

I was talking with one of my Computer Science students (who’s taking Chemistry with one of my colleagues) about ChemQuiz.net and he told me how frustrated he was when he accidentally pressed the “enter” key and submitted his answers before he was done with the quiz, and he had to start all over. I felt that he made a really good point, so I looked into adding a popup window or a modal dialog box to verify that a student was ready to submit their answers, but I found that the least disruptive way to prevent accidental submission would be to disable the “enter” key altogether.

This means that in order to have their responses graded, students must now click the pink “Grade it!” button. I’m hoping this eliminates any frustration your students may have experienced with this issue! Please let me know if you notice any problems with this change, or if your students encounter any other difficulties or issues while using ChemQuiz.net.

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Lots of bug fixes

It’s difficult to find the time and mental energy to sit down and focus on fixing bugs on ChemQuiz.net while school is in session, especially when some of the code was written a long time ago back when the quizzes were on my school blog. That’s why I tried to focus on knocking out as many as possible during this winter break so that the site runs as smoothly as possible for the rest of the school year. Here’s a list of everything that has been fixed recently

Dashboard

• when creating a new assignment, the “Require student login” setting was saving as “checked” even when unchecked
• student quiz result times were not adjusting correctly for the school’s time zone on Results and Grades pages
• clicking on the “Results” link on the Students page would not show that student correctly on the Results page

Bond Polarity & Electronegativity Quiz

• entering “0” for electronegativity difference (Δχ) now correctly registers as “0” instead of “no answer” (thanks to my students!)
• added “fuzziness” option of +/- 0.1 for electronegativity difference (Δχ) values (also suggested by my students)

Hess’s Law Quiz

• incorrect heat values were being pulled from the database when grading (thanks Terrie, Thomas and Elena!)

Mass Ratios, Percent Composition & Empirical Formulas Quiz

• empirical formulas with polyatomic ions are now counted as correct (thanks, Scott!)

Molar Conversions Quiz

• answers less than 0.01 were showing up as 0 but not being accepted (thanks Scott, Theresa, Danny and Carol! I’m really sorry that this bug caused so much frustration to so many people)

Molecular Geometry & VSEPR Quiz

• changed wording to “unbonded electron pairs *around the central atom*” (thanks, Susan!)

Naming Compounds & Calculating Molar Masses Quiz

• also accepts “aluminium” for compound names (suggested by one of my students who used the IUPAC spelling from her periodic table)
• H₂O₂ and O₃ are no longer included in the quiz

Periodic Trends Quiz

• added multiple choice questions
• added option to select representative elements (s- and p-blocks) and/or transition metals (d-block)
• quiz wasn’t available in the Dashboard (thanks, Rohunke!)

Other improvements

• fixed columns in the Useful Equations handout
• additional “under the hood” improvements

If I didn’t fix a bug or issue that you’ve reported, I’ll do my best to address it as soon as I can!

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Help with new rate laws quiz?

I’ve received several requests over the past couple years to write a quiz on kinetics and rate laws, but I have to admit that I’ve never really taught it, so I don’t have a deep understanding of it, and I don’t have a lot of resources beyond what I can find online and in the textbooks that I have laying around. In order to write a dynamically generated quiz, I need to be able to visualize the kinds of questions and problems it would generate based on repeating patterns, so the more types of problems I can see and categorize, the better.

If you have any good materials that you’d be willing to share with me, such as worksheets or assessments (especially with keys!), I would very much appreciate it, and I promise not to share them with anyone else! It doesn’t have to be anything fancy; even a quick picture of a worksheet would help. Thanks in advance!

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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!

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

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Here’s hoping that 2023 is a great year for all of us! Please contact me any time if you have any questions or suggestions for improvement, or if you run into any problems while using ChemQuiz.net. Take care, stay safe, and as always, thanks so much for your support!
-Chris

Hello, everyone! I hope your new school year has started off well with as few bumps and disruptions as possible. Despite enduring two lockdowns at school last month, I’m having a lot of fun teaching Chemistry again because I get to do neat stuff like making “gold” pennies:

This is from the Alchemy Lab that I’ve been doing for decades and which is a student favorite – here are the directions if you’re interested! There are lots of ways to do the lab, but this year I had my students heat their pennies on hotplates instead of in Bunsen burner flames, and that seemed to work much better. (On a side note: today when I was testing Bunsen burners and bleeding air that had built up in the gas lines in the lab over the summer, one of them suddenly shot flames out from the bottom and burned off some of the hair on my knuckles, so I’m happy to stick with hotplates instead! 🔥)

Since the start of September, over 20 schools have either signed up for new site licenses or renewed from last school year, so I wanted to thank you all for your continued support of ChemQuiz.net! These site licenses allowed me to upgrade to faster web hosting last month to make the site run faster. Speaking of the upgrade…

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September 21st hosting upgrade (or, “The best laid plans of mice and men”)

I’ve noticed that the site was getting WAY more traffic in August 2022 than it did in August 2021, and there were more issues with “site not responding” errors due to my web hosting tier being overwhelmed, so I used money from site licenses to upgrade my web hosting. Based on the documentation on my hosting service’s website, it seemed really easy – contact sales, pay for the upgrade. The process probably took me a total of five minutes, at most!

Unfortunately, the sales team must not have communicated with the tech support team, because while the guts of ChemQuiz.net got moved to a new server and IP address, none of the domain name service (DNS) entries got updated, so for about 24 hours, loading up ChemQuiz.net would take you to the old server, not the new one that I’d paid for. When I finally realized what was going on the following day, it took about two hours of tech support chat and phone calls to get everything sorted out.

Without getting into the gory details, DNS updates propagate across the world from the server they’re originally changed on, one server connection at a time, so it can take up to 48 hours for the changes to take effect everywhere in the world. This means that for about a day and a half, some users were accessing the new, faster ChemQuiz.net hosting, while others were accessing the old, slower hosting. The quizzes all acted the same, but some quiz results were saved to the old server and then “disappeared” as soon as the DNS update went through.

The good news is that I still had access to the old server, so I waited until DNS had fully propagated by Saturday afternoon and then copied those missing results over to the new server. I only copied over important quiz result and user data, so you can see switchover clearly on this graph of site visits over the last 20 days since I didn’t bother copying the database table with those stats:

If it still appears that any of your students’ quiz results are missing from the Dashboard, please let me know and I’ll double check for you! I know how much students hate it when a teacher loses their work, so I don’t want that to happen to any of your students on ChemQuiz.net.

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Student login issues

I’ve been hearing from a number of teachers with site licenses to the Dashboard that their students are sometimes having problems accessing ChemQuiz.net during the day. There are two primary reasons this has been happening: an overall increase in the number of visitors to the site, and the security software interpreting failed student logins as hacking. I’ve upgraded the web hosting to address the first, as I mentioned earlier, but the second issue is a little more complicated.

Basically, if a student repeatedly attempts to log in with an incorrect password (or no password at all) and fails 10 times in a row, the site’s security software will block that student’s IP address for 5 minutes. The idea is to prevent “brute force” hacking, which unfortunately is very common on sites like ChemQuiz.net that are based on the WordPress content management system. (You would not believe how frequently the website is attacked from all over the world – it’s a constant issue.) This student behavior may be unintentional or completely intentional, but the effect is the same, and it can prevent your other students from accessing the site if they have the same IP address, which is common for school districts.

Unfortunately, I can’t disable the security software, because ChemQuiz.net would get hacked within days, if not hours. However, to prevent this sort of lockout from happening to you and your students, there are two steps you can take. First, you can send me your school or district IP address at school by googling “What’s my IP address” and send me the number. I’ll whitelist your IP address so that any failed login attempts are ignored by the site security software. Make sure you do this at school, not at home! The second thing you can do is monitor your students when they’re logging in to ChemQuiz.net to make sure they’re not just clicking the login button repeatedly. The good news is that their login sessions last for 30 days since the last time they’ve accessed the site, so between that and the “Login with Google” button, I’m hoping this won’t continue to be a serious issue going forward.

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New features & bug fixes

No new quizzes with this update, but thanks to your feedback, I’ve made some serious bug fixes that were impeding assignment creation on the Dashboard. Here’s a summary of the bug fixes:

• disabled autocomplete in all form inputs for all quizzes so that entering answers is a cleaner experience for students (suggested by my son!)
• students couldn’t load all of the options to practice a quiz if an assignment already existed for it (thanks, Danny!)
• threshold, notes, instructions and custom name were being wiped out in the database when a new assignment was created in the Dashboard (thanks, Ryan!)
• “lock after close” could be set without a value for “date closed” when creating & editing assignments (thanks, Krisha!)
• can’t edit quiz-specific options for an assignment in the Dashboard if it has a due date (thanks, Darlene!)
• archived classes were showing up in filter menu on the Results page in the Dashboard (I found this one)
  
• + other under-the-hood Dashboard improvements
• answers on the Concentrations of Solutions Quiz that were correctly rounded to the hundredths place were marked as incorrect (thanks, Karen!)
• the Lewis Dot Structures Quiz wasn’t identifying all correct student responses, so now the quiz just counts the number of checkboxes to match the correct number of valence electrons (thanks, Nick & David!)
• some two-step conversion problems in the SI Conversions Quiz were converting to the same unit 🤦🏻‍♂️ (thanks again, Darlene!)

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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!

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

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There was a funny moment this weekend when our oldest kid, who’s a first-year student at Ohio University, was visiting us up in Kent this past weekend. Our son is a freshman taking Advanced Chemistry with a colleague of mine at the high school where I teach, and he was complaining about how he missed some questions on a recent sig figs quiz in class. Unprompted by me, our oldest said, “Use ChemQuiz to practice sig figs, it’s easy!” I wish I’d had my phone in hand so I could have recorded the exchange for future advertising purposes, but all I have is the memory. 😂

Thanks again to everyone for your continued support of ChemQuiz.net and for your patience with the bumps in the road that have occurred recently. Please feel free to get in touch with me if you have any questions, suggestions for improvement, or problems with the site. Take care and stay safe!

-Chris

PS: If you didn’t see the September newsletter because of email delivery issues, it’s available here!

Good afternoon, and Happy Labor Day to all of my fellow Americans! For those of you who have started school already, like I have, I hope everything has gone smoothly so far, and for those of you about to start, I hope it goes well. As I mentioned in a previous newsletter, due to resignations and staff reductions at my school, my Climate Science and AP Physics 2 courses were axed and I was switched back to teaching CP Chemistry for the first time since the 2013-2014 school year. I’ve been surprised to find that I’ve been able to get back into the groove pretty quickly after only two weeks with my Chem students. I’m pretty sure that writing and tweaking the chemistry practice quizzes for ChemQuiz.net have kept that knowledge in the forefront of my brain! Teaching Chemistry again also allows me to do fun demos like this:

If you’re interested in doing this demo, simply add 0.1M HCl to a test tube until it’s about 2/3 full, add enough universal indicator to make it really red and stir, then hold the test tube at an angle and add saturated sodium carbonate (also known as “washing soda”) dropwise. The sodium carbonate is more dense than the hydrochloric acid, so it slides right down the side of the tube and raises the pH so that it turns dark blue. This was a real showstopper when I did it in class last week, and it leads to all kinds of great questions and discussions, so I highly recommend it for all levels!

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5 million visits!

This past Thursday, September 1st, ChemQuiz.net broke 5 million visits since the site went live in June 2020! On the same day, the site set a new record for total vists (40,752) and unique visitors (3,749). The record from the 2021-2022 school year was 30,520 visits on February 8th, 2022, so I’m expecting another year of exciting growth for the site. Since the site is currently averaging just under 4 million visits per 365 days, I’m wondering if it’ll hit 10 million visits by the end of this school year. Maybe! Either way, I’m absolutely flabbergasted by the numbers and how much the site is being used.

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Site licenses

Thank you SO MUCH to everyone who has purchased a site license for their school for the 2022-2023 school year! I truly appreciate your support and trust as we’re all gearing up for a third year of pandemic teaching. For those of you haven’t purchased a site license yet, make sure you check your demo expiration date by logging in to the ChemQuiz.net Dashboard and clicking on “School Info” in the top menu. I extended a number of demo accounts through the end of September, so if you’re thinking about purchasing a site license, you have until then to play around with all the Dashboard features.

If you’re interested in purchasing a site license for the 2022-2023 school year, the cost is US$50 per year per school or college instructor, and I can accept payment through school purchase order, personal check, credit card through Square, or CashApp, PayPal, Venmo and Zelle at chris@chemquiz.net. If you’re outside the United States, please use one of the electronic payment methods above. If you teach in a high poverty public high school or school district (at least 50% of your students on free/reduced lunch or designated “economically disadvantaged”), then send me a link to the supporting documentation and you’ll get a site license for free forever. I’m still strongly committed to making ChemQuiz.net a part of leveling the playing field for STEM students around the United States!

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New quiz!

*NEW* Laboratory Equipment Quiz!

• 75 items and OSHA safety symbols commonly found in the chemistry lab with names, diagrams and descriptions
• excellent equipment diagrams from Chemix! (used with permission)
• fill-in-the-blank option for naming equipment and safety symbols; multiple choice options for diagrams and descriptions

This quiz was a lot of fun to write, and now that I’m teaching Chemistry again, I’m looking forward to using it with my own students to see how much it helps them learn all of the different lab equipment that we have. We spent an entire school day this past Friday with every Chemistry student emptying out the lab drawers, sorting the equipment, cleaning the glassware and drawers, and restocking the drawers with the correct kinds and amounts of equipment in our two chem classrooms. We found some stuff that had been in there for close to a decade, if not longer. 😳 Thanks to Susan for the quiz suggestion!

New features & bug fixes

Between getting ready to teach Chemistry again and trying to organize the diagrams and descriptions for the Lab Equipment Quiz, I focused on adding new features that have been requested by teachers and also on fixing bugs that either caused serious problems or gave users a weird experience. Some of these requests go back over a year, so I apologize if yours took a while to complete!

New Dashboard features & bug fixes

• looking at the detailed assignment result will now show all attempts by that student for that assignment to show growth (if any)
• teachers can now generate a printable or presentation version of an assignment with their selected settings from the Assignments page (thanks Barry!)
• teachers can now add students to a class through the “Bulk actions” menu on the Users page
• added a file attachment field to the Contact form for screenshots to make it easier to report bugs
• bug fix: CSV user import from a Google Sheet wasn’t working because Google changed its access parameters for Sheets
• bug fix: CSV import should handle apostrophes in student names correctly now
• bug fix: lost password link was hijacked by the WooCommerce plug-in (thanks Rhonda!)
• bug fix: the “requireLogin” setting for assignments had the wrong name in checkbox 🤦🏻‍♂️ (thanks David!)
• bug fix: copying an assignment in the Dashboard produced an error due to a bad MySQL query (thanks Barry!)
• bug fix: adding student accounts by CSV import wasn’t adding students to classes because of a string misspelling 🤦🏻‍♂️🤦🏻‍♂️

New quiz features & bug fixes

General updates

• added CONFETTI for when a student earns an achievement or a perfect score on quiz with 10 or more items (I know this one is silly, but it makes me laugh every time I see it so I hope your students like it too – you can preview the confetti if you’re curious!)
• made “under-the-hood” improvements for various quiz functions
• bug fix: quiz options logging was slowing down the site significantly, so I turned it off until I can improve its performance (logging is only to see how often certain options are being used, it doesn’t track users)
• bug fix: turning off session_start() in the logging function allowed students to go back after submitting quiz, so I re-enabled PHP sessions (thanks Anamar!)

Balancing, Identifying & Predicting Chemical Equations Quiz

• added multiple choice questions (I hope to do this someday for all the quizzes, but it can be really challenging to come up with good distractors that are dynamically generated)
• added physical states to chemical equations (thanks Don!)

Bond Polarity & Electronegativity Quiz

• bug fix: delta notation was giving wrong answers (thanks Matthew!)

Calorimetry Quiz

• added “drop hot metal into cold water, what’s the final temperature?” problems (thanks Ken & Sylvie!)
• added ~20 specific heats of metals to the database

Density Calculations Quiz

• added g/L and kg/L density units (thanks Sylvie!)

Gas Laws Quiz

• made the wanted value more obvious with listed givens
• bug fix: gas names weren’t showing up with listed givens

Mass Ratios, Percent Composition & Empirical Formulas Quiz

• added “percent composition from masses” and “empirical formula from masses” questions (thanks Holly!)
• added an option for word problems

Naming Compounds & Calculating Molar Masses Quiz

• added an option for compounds with common polyatomic ions (thanks Barbara!)
• made the random selection of givens more evenly distributed (thanks for the suggestion Grant! Over time I’m going to go back and implement the code I developed for this to all of the quizzes)

Organic Nomenclature Quiz

• added aromatic compounds
• bug fix: compounds with rings and halides were not being selected properly

Redox Reactions & Net Ionic Equations Quiz

• changed question wording so that it says “substance” instead of “compound” (thanks Matt!)

Scientific Notation Quiz

• added challenging “determine prefix” problems
• added counting the number of sig figs in the answer (thanks Carla!)
• bug fix: quiz wasn’t handling × (times symbol) correctly in answers (thanks Joseph!)

Significant Figures Quiz

• bug fix: gave the wrong answer for addition/subtract problems when both givens had decimal points (thanks Kelli!)

Stoichiometry & Limiting Reagents Quiz

• added physical states to chemical equations (thanks Don!)

Thermochemical Equations Quiz

• added physical states to chemical equations (thanks Don!)

Thanks again to everyone who made suggestions or reported bugs so that I could make these improvements! If you have an idea for a new feature or quiz, or you come across something that’s not working correctly, please let me know by emailing me at chris@chemquiz.net, or you can fill out the easy-to-use Contact form.

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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!

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

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In mid-August, we moved our oldest kid into the dorm for their first year at Ohio University, where they’ll be majoring in Wildlife Conservation Biology while also playing flute in the symphonic band (because flutes aren’t allowed in the OU marching band – go figure!), so our house feels a little emptier than usual. If you’ve been through this milestone, then you already know the weird mixture of emotions it can bring. Personally, like a typical dad, I’ve been keeping myself busy working on ChemQuiz.net so I don’t have to confront my own feelings. 😂

I know I’ve said it many times, but thanks again for all of your support – whether you just signed up this week or you’ve been collaborating with me for the past decade – because it makes this little venture all the more enjoyable. Please feel free to reach out any time if you have any questions, concerns, suggestions or feedback. Take care, stay safe, and good luck this school year!

-Chris

Hi, everybody! I hope you’re all doing well and have been able to get some rest and relax a bit after the challenges we faced this past school year. On a personal note, I was able to take the family up to the Upper Peninsula of Michigan for a few days in July – what a beautiful place! We stayed in the tiny town of Grand Marais on the southern shore of Lake Superior for a few days and took in some of the local sights. If you’re ever able to make it up there and you like seeing trees more than having cell service, I highly recommend it!

I’ve put a lot of time and effort into ChemQuiz.net this summer to write new quizzes and improve the Dashboard so that the site is more useful for you and your students this upcoming school year. I’m really excited about all the new stuff I have to share with you, so let’s get right to it!

New quizzes!

*NEW* Bond Polarity & Electronegativity Quiz

• determine polarity, arrow notation and delta notation of chemical bonds
• calculate electronegativity difference (Δχ or ΔEN)

*NEW* Molecular Geometry & VSEPR Quiz

• identify molecular shape, electron geometry and AXE notation of chemical compounds
• determine polarity, ideal bond angle(s), electron hybridization and number of domains, unbonded pairs and total valence electrons

*NEW* Organic Nomenclature Quiz

• name organic compounds from over 9,000 chemical diagrams
• identify organic compound classes such as alcohols, aldehydes, amines, esters, ethers, ketones and more

*NEW* Redox Reactions & Net Ionic Equations Quiz

• write net ionic equations when given chemical reactions
• determine oxidation numbers in over 1,000 compounds and identify oxidizing and reducing agents in reactions
• balance over 100 redox reactions in acidic and basic solutions

I had a lot of fun writing these quizzes and learned a lot while working on them, from AXE notation to using PubChemPy to interface with PubChem to drawing molecules with SMILES. I feel like they fill in some of the gaps in topics that I had before and I hope they provide you and your students with lots of useful practice questions!

New features

I received some really helpful feedback from the end-of-the-year survey that I sent out last spring about how the Dashboard could be better, so I’ve made the following improvements:

New Dashboard features for teachers:

• NEW “Gradebook” feature provides easier to read results in a grid
• NEW Teacher Discussion Forum for communicating with other Chemistry teachers around the world – ask for help, point out bugs, etc! (FYI you must be logged into your teacher account to access the forum)
• moved the sample curriculum to Dashboard as “Exemplars” (more on this in a bit)
• teachers can now create assignments that don’t require students to log in – great for quick check for understanding or “bell ringer”! – just share the link with them
• teachers can now require an access code for assignments – helpful if you have multiple sections of the same course throughout the day and want to restrict access
• added a checkbox at the top of the Results table to select all results so teachers can archive them in a bulk action
• teachers can now see which students have started an assignment but haven’t finished

Because of some personnel changes, the school where I teach switched me back to Chemistry again – for the first time in eight years! – so that made me really sit down and think about how to make the Dashboard work better for classroom teachers who have limited time to figure their way around a complicated user interface, so I really hope the improvements are noticeable and helpful.

More new features for teachers:

• users can log in through Google using the “Log in with Google” button on the Login page – if your district uses Google, this should help your students who have login issues!
• custom assignment names now show at the top of quizzes
• added “Name:” line & custom title options to the top of printable quizzes

New Dashboard features for students:

• added a menu bar for better organization
• students can now change their own password
• added a big pink “Go to Dashboard” button on home page that shows up if they’re logged in
• cute new artwork by Rain Carman for Significant Figures Quiz and Gas Laws Quiz!

Our school district uses Google and my son is taking Chemistry this year with one of my colleagues, so I’ve been testing the Google login with him and I’m hoping it’ll make the site a lot easier to use for everyone in the Google ecosystem.

Bug fixes

Unfortunately, there will always be bugs with any software, but I’ve been able to fix a number of them thanks to the help of many teachers and students:

• automated assignment and result emails are working properly again!
• filter menu for assignments Results didn’t show all assignments if any archived results existed for that teacher (thanks Jason!)
• couldn’t remove “Assignment due date” on existing assignments (thanks Matthew!)
• Scientific Notation Quiz wouldn’t load proper settings in printable mode
• Solubility Quiz wasn’t calculating answers for ions correctly (thanks Susan!)
• Enthalpy Calculations Quiz wasn’t calculating answers for mass (g) correctly (thanks again, Susan!)
• percent yield problems in the Stoichiometry & Limiting Reagents Quiz with a given product and wanted reactant quantity were not calculating correctly (thanks Don!)
• many other small fixes and under-the-hood improvements and optimizations

I still have a few more bugs I’m trying to track down and squish before my school year starts in the next couple weeks! If you come across something that’s not working properly on ChemQuiz.net, please let me know by emailing me or filling out the Contact form on the site. Sometimes I can find and fix a bug quickly, while other times it takes me a while to reproduce the error and figure out what it’s happening, but rest assured that I document them all and will try my best to resolve them.

NEW Independent Student Accounts!

I’ve always tried to make ChemQuiz.net as accessible as possible by making the quizzes free for everyone to use and giving out free site licenses to schools with high proportions of economically disadvantaged students. However, I’ve been contacted in the past by students whose teachers aren’t using the ChemQuiz.net Dashboard but want to work on their own and keep track of their own progress, especially when preparing for an exam.

To that end, I’ve created a new Independent Student Account option that features over 150 scaffolded assignments across the 30 quizzes on the site! As students complete the assignments, they’ll earn “Achievement Badges” based on the number they’ve passed as well as the quizzes or topics they’ve finished. Students can also hide topics that don’t apply to their studies; for example, I imagine a lot of high school students will hide the Organic Nomenclature assignments. Here’s what independent students will see when they log in:

Here’s a picture of the “Neon Badge”, which an independent student will earn after completing 10 assignments:

(atomic #10, get it? 😂)

I’m hoping that Independent Student Accounts will help make ChemQuiz.net even more useful to Chemistry students around the world, regardless of whether their teachers use the Dashboard, so I’m keeping the price low at just US $6 for a full year of access. As I write more quizzes and add more features to existing quizzes, I’ll keep creating assignments that will be available at no additional charge. Please reach out if you have any questions about Independent Student Accounts!

By the way, these assignments are available for teachers with Dashboard site licenses to use too! Just log in to the Dashboard and click on the new “Exemplars” link in the top menu bar:

From there, you can select an exemplar (example assignment) and create a copy of it to assign to your own students and modify however you’d like. These are many of the same assignments I plan on using in my CP Chemistry classes this upcoming school year, so I hope they’re also helpful for you!

Dashboard site licenses for the 2022-2023 school year

A number of you have already purchased a site license to the ChemQuiz.net Dashboard for the 2022-2023 school year – thanks again for your support! Site licenses help me pay for the web hosting and other software that I use to write and publish the quizzes. They also help me justify the time I’ve spent developing the site instead of applying for more supplementals at school (like I’m sure many of you have done!). Site licenses are good through July 1, 2023, unless your school district operates on a different academic calendar, in which case I can modify that access window to meet your needs.

If you’re interested in purchasing a site license for the 2022-2023 school year, the cost remains US$50 per year, and I can accept payment through a variety of means, including school purchase orders, personal check, a credit card through Square, or you can send payment to chris@chemquiz.net at CashApp, PayPal, Venmo or Zelle. If you’re outside the United States, please try to use one of the electronic payment methods above, as my credit union has made depositing foreign checks difficult.

I’ve sent out a lot of sales quotes and invoices recently, but if you didn’t receive one or need another copy, please let me know! If you’re planning on paying with a school purchase order, I’m happy to fill out whatever forms your district requires and I’ll activate your site license as soon as I get the PO.

Remember, if you teach in a high poverty public high school or school district (at least 50% of your students on free/reduced lunch or designated “economically disadvantaged”), then just send me a link to the supporting documentation and you’ll get a site license for free forever. There are currently 73 public schools in the United States that are taking advantage of the free site license to help their students learn Chemistry, and it makes me really happy that I can offer that service to them at no cost.

Help get the word out about ChemQuiz.net!

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

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

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Collaborating with science teachers all around the world over the past two years has been the most rewarding aspect of creating ChemQuiz.net (although I did get a really nice email from a student who told me that, thanks to the site, she passed Chemistry and was planning on majoring in it, so that might win!) so I wanted to thank you for all of your kind words, helpful suggestions and constructive criticism. With all of the modern classroom stresses of bed bugs, covid, school shootings and now monkeypox, it’s nice to have something positive like this that I can focus my efforts on. I’m looking forward to another great school year of serving up Chemistry practice quizzes!

-Chris