ChemQuiz.net

Hello again! I hope everyone has had a good start to the school year, and if you’re in the United States, you’ve been able to take some time to relax and enjoy Labor Day weekend.

In this newsletter, I’ve included important information about these topics:

• New student account creation features
• Issues with website security software
• New features & bug fixes
• Site licenses for the ChemQuiz.net Dashboard (and PhysQuiz.net!)

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New student account creation features

So far, teachers have already created 6,322 new student accounts for the ChemQuiz.net Dashboard since July 1, 2023. For the entire previous school year, there were 12,333 student accounts, so we’ve already added over half as many as last year, and September just started! 😱

While most student accounts have been created without any problems, there have been a few issues that have popped up that have been brought to my attention by a number of teachers. One of the main issues is that students never receive a registration email that allows them to set their password because their district blocks outside emails.

To try to resolve this issue, I’ve added two new features that I think will help:

1. Students can now set their password when they’re using a join code. This solution is so obvious that I don’t know why it took me so long to think of it. 🤦🏻‍♂️ Once a student has successfully created their account, they can go to the Login page and get started in the ChemQuiz.net Dashboard immediately.

2. Teachers can now set student passwords when creating accounts with a CSV file. If you use another LMS like Google Classroom or Canvas, or an online gradebook like ProgressBook, you can export your list of students as a CSV file (“comma separated values”) and add a column for passwords. You can also make a copy of the Google Sheet that I’ve created for this purpose and enter your students’ email addresses, names and passwords, and then export it as a CSV or get the share link and use that in the ChemQuiz.net Dashboard to import your student accounts. (Thanks for the suggestion, Chris!)

Also, if your school uses Google for Education, encourage your students to use the “Log in with Google” button! Unfortunately, I’ve heard from two teachers who have encountered an error that says “Access blocked: Your institution’s admin needs to review ChemQuiz.net” when students try to log in. If you see this message, you’ll need to get in contact with your district’s tech support to get this resolved in the Google Admin panel.

Don’t forget: you can manually set student passwords in the ChemQuiz.net Dashboard, and you can also generate random passwords for them using the “bulk actions” menu on the Students page.

I’m hoping these new features make the onboarding process a little bit easier for you and your students! However, if you encounter any issues, please reach out to me and I’ll be happy to help you.

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Issues with website security software

As I mentioned in last month’s newsletter, I migrated ChemQuiz.net to a new web hosting company in early July so that I could improve the site’s speed and reliability. I’ve been really happy with their support staff, and they’ve been extremely helpful (and patient!) with resolving the issues that typically occur whenever a site migrates. It was definitely the right decision to move.

Having said that, there have been a few glitches due to their robust security software. Combine that with the additional security software that I’m running, and there have been a number of “false positives” that have prevented students from completing assignments or being able to access the site at all.

Thanks to the detailed emails and screenshots from a number of teachers, I’ve fixed several of the “Forbidden” errors that teachers and students have experienced recently, particularly with the Naming Compounds & Calculating Molar Masses Quiz. If you come across one of these errors, please let me know the date and time that it happened to you so I can track it down in the server logs. The more details you can send me, the better.

Another issue that a number of schools have experienced is when the Wordfence security software blocks them entirely from accessing the site. This happens when too many students try to log in with an incorrect password and the school or district is behind a proxy that makes all of the individual student devices look like one IP address. I’ve relaxed a lot of these settings but I can’t disable them entirely because the site is under attack on a regular basis, like most websites are.

I’m hoping that the new student account creation features will decrease the number of failed login attempts, but in the meantime, if you’re about to onboard your classes, try googling “what’s my IP address” while you’re at school and send me the result. That way, I can add your school’s IP address to a whitelist so that it’s ignored by some of the security software, which makes it less likely that you’ll get blocked. It’s not an ideal solution, but it works!

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New quiz features & bug fixes

There are no new quizzes this month, but I’ve added some new features and fixed some bugs to help ChemQuiz.net run more smoothly for you and your students.

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

• added ability to set student password on CSV upload or when creating account (thanks, Chris!)
• quiz completion time was sometimes saved using local timezone instead of UTC (thanks, Racquel!)

All Quizzes

• added quiz option headers to some quiz forms so the options are better organized
• teachers can now prevent students from seeing scores or correct answers in an assignment (thanks, Jennifer & Laura!)

Chemical Equilibrium Quiz

• added an option to only include Kc equations
• added an option to use Keq label for all problems (thanks, Helen!)

Chemical Thermodynamics Quiz

• quiz gave an empty settings error for mass/moles even if the question type didn’t require it

Elements & Isotopes Quiz

• isotope notation SVGs weren’t displaying (thanks, Mary Ann!)

Kinetics & Rate Laws Quiz

• added more granular question options (e.g., disable the instantaneous rate option) (thanks again, Helen!)
• fixed solution for instantaneous rate law so that it uses values from the given table (thanks, Susan!)

Naming Compounds & Calculating Molar Masses Quiz

• Apache ModSecurity rule was preventing submission of answers for large quizzes (25+ questions) (thanks again, Mary Ann!)

Solubility Quiz

• mercury(II) hydroxide was entered incorrectly in the database (thanks again, Mary Ann!)

Other new features and bug fixes

• added ability for students to set password on registration form with join code
• creating a student account with join code for inactive class may create a user associated with a non-existent school
• school join codes weren’t being recognized properly (thanks, Blake!)
• Apache ModSecurity was preventing submission of URLs on Teacher Interest form

I keep track of every bug or issue that gets reported as well as every new quiz suggestion that’s sent in, so I’ll continue to address those as they come in. New features and quizzes can take a while to develop properly, and some bugs are easier to fix than others, so I appreciate your patience! ChemQuiz.net has improved significantly over the past three years thanks to all the teachers and students who have sent in reports, so please keep sending them in!

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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 so much to the 66 schools and tutors who have renewed or purchased a site license for the 2023-2024 school year! Site licenses are also how I pay for the web hosting and the software I use to write the quizzes, and it keeps the website ad-free.

If you’d like to purchase a ChemQuiz.net site license for the 2023-2024 school year for just US$50, you can pay in the following ways:

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

Remember, site licenses are by building, so one license applies to every teacher and student in your entire school! Additional schools in the same district can purchase an add-on license for just US$25 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$25 more! Please contact me if you have any questions about how to purchase a site license.

One last thing – 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!).

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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!

• Add your school to the list of supporters on the About page! Go 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.
• Tell another Chemistry teacher about ChemQuiz.net and encourage them to try out the Dashboard!
• Follow @ChemQuizDotNet on X (Twitter), Facebook and Threads and share my updates with your fellow Chemistry teachers!

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I hope the school year has started well for everyone so far! After mild temperatures and lots of rain in northeast Ohio for most of the summer, we’re looking at a heat wave this upcoming week that’s going to push the limits of our HVAC systems. I just moved to a new classroom that used to have the best air conditioning in the building, but for some reason it suddenly stopped working this summer! 😩I might have to take my afternoon classes on a spontaneous tour of the walk-in freezer next to the cafeteria just to make it through the heat.

Thanks again for your support of ChemQuiz.net! Please reach out any time via the Contact form or at chris@chemquiz.net if you have any questions, comments, or concerns. Take care!

-Chris

Welcome back! I hope those of you who were on summer break got lots of rest and relaxation so that you’re ready to tackle the upcoming school year.

In this newsletter, I’ve included important information about the following topics:

• *NEW* Chemical Thermodynamics Quiz!
• *NEW* website: PhysQuiz.net!
• Upgraded web hosting for faster quiz loading
• New features & bug fixes
• Site licenses for the ChemQuiz.net Dashboard

There’s lots of new stuff to cover, so let’s get started!

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*NEW* Chemical Thermodynamics Quiz

• determine change in entropy (ΔS°) and Gibbs free energy (ΔG°) in chemical reactions
• determine if chemical reactions are spontaneous or nonspontaneous
• calculate chemical equilibrium constants (K) and reaction quotients (Q) from free energy values
• aligns with Next Generation Science Standards Performance Expectations “HS-PS1-4:  Matter and its Interactions” and “HS-PS3-1: Energy”

This new quiz should help your students in advanced or second year Chemistry courses to get a better grasp on some really challenging thermodynamics concepts, so check it out and let me know what you think. Thanks to Kristen for suggesting the quiz!

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*NEW* website: PhysQuiz.net!

I’ve spent most of the past two months writing new quizzes for a brand new sibling site – PhysQuiz.net! There are a total of thirty-one free practice quizzes in a wide range of categories:

• Science Fundamentals
• Kinematics (position & motion)
• Dynamics (forces, momentum & energy)
• Circular Motion and Gravitation
• Electricity and Magnetism
• Waves & Optics
• Thermodynamics
• Modern Physics

PhysQuiz.net uses the same Dashboard as ChemQuiz.net, so you’ll still have the ability to create assignments with the settings you choose and collect quiz results from your students. You can fill out this short form to sign up for a free 30-day demo of the PhysQuiz.net Dashboard!

I tried to cover the topics that are found in a typical first-year algebra-based high school Physics course that align with the NGSS Performance Expectations, but I’m also planning to add quizzes this upcoming school year for fluids as well as more thermodynamics and modern physics. Our school brought back AP Physics 2 and I’m teaching it again, so I’m highly motivated to add those topics! I also want to add more diagrams and graphs to the quizzes, because I learned a lot about scalable vector graphics (SVGs) while writing the Vector Calculations and Motion Graphs quizzes, and I’m really happy with how they turned out.

Just like ChemQuiz.net, a full site license for the PhysQuiz.net Dashboard is US$50 per school year, and I offer discounts for multiple secondary schools within the same district or multiple instructions within the same college or university. If you also subscribe to the ChemQuiz.net Dashboard, you’ll get a 50% discount so that PhysQuiz.net is only US$25 per school year! Current subscribers can use Square to purchase an add-on license here, or you can purchase licenses for both sites here. I can also accept payment through a variety of other methods, including school purchase orders, so please reach out if you want to get that process started or have any questions.

I want PhysQuiz.net to be useful to as many teachers and students as possible, so if you teach at a high poverty public high school or school district with at least 50% of your students on free/reduced lunch or labeled “economically disadvantaged”, you qualify for a free site license! Just fill out the PhysQuiz.net Dashboard interest form and include a link to your school’s demographic information. I’ll also be running a separate monthly newsletter for PhysQuiz.net, so if you’re interested in news and updates about the site, please fill out this short form or send me an email at chris@physquiz.net to sign up!

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More powerful web hosting for ChemQuiz.net

In mid-July, I migrated ChemQuiz.net to a new web hosting company (Scalahosting, for those who are interested) and upgraded to a “virtual private server” that gives ChemQuiz.net way more speed and power than it ever had before! As the site has become more popular, it was obvious that it had outgrown its humble beginnings and needed more resources.

For example, this past school year (July 1, 2022 to June 30, 2023), 9038 students from 118 schools completed 2393 different assignments given by 143 different teachers for a total of 152,668 quiz results. To put it in perspective, that’s seven times as many quiz results as the previous school year, and that only counts students who completed assignments through the ChemQuiz.net Dashboard!

If you were using ChemQuiz.net with your students this summer during the week of the site migration, I really appreciate your patience as I did my best to work out some of the weird, unforeseen issues that popped up as a result of the move. I believe it’s going to put the site in a much better position to keep providing practice quizzes to science teachers and their students all over the world!

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New quiz features & bug fixes

In between writing 22 new physics quizzes 😅 and migrating the entire website 😵‍💫, I was able to add some new features to ChemQuiz.net and also fix some bugs:

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

• added a “last access” parameter in the Dashboard so teachers can see when students last used the site
• added the ability for teachers to use preview, printable and presentation modes on exemplar assignments
• fixed a bug where preview links were broken on the Assignments page
• fixed a bug where sharing an assignment with a colleague would exclude specific quiz options (thanks, Helen!)
• fixed a nasty bug where custom assignment names, instructions to students and notes were truncated whenever apostrophes or quotation marks were used
• fixed a bug on the Grades page where the chosen class was “forgotten” when clicking the “Next>>” button (thanks, Don!)
• fixed a bug where class status (e.g. “Active” or “Inactive”) wasn’t showing up on the Classes page
• fixed a bug where selecting “lock after close” for an assignment that had no closing date would prevent students from taking the assignment
• fixed several other minor appearance and user experience bugs

All Quizzes

• sometimes when a student entered a number in scientific notation incorrectly, the quiz would show their entry as “1f x 10”, so now it shows what they entered without attempting to reformat it (thanks, Mary Ann!)
• teacher instructions in some assignments were incorrectly triggering a false positive in the site’s security software (thanks, Don!)
• added “(where applicable)” to solution setup directions for some quizzes

Acid-Base Equilibrium Quiz

• pH was incorrectly calculated as 14 when given a concentration and % ionization in certain situations involving bases  (thanks, Mary Ann!)

Calorimetry Quiz

• option to show solution setups wasn’t activated (oops!)
• exemplar assignments were not displaying selected options in the Dashboard

Nuclear Reactions Quiz

• positron decays with additional products were generating too many nuclides
• exemplar assignments were not displaying selected options in the Dashboard

Stoichiometry & Limiting Reagents Quiz

• added an option to show molar masses in questions (thanks, Monica and Malcolm!)

Thermochemical Equations Quiz

• added an option to show molar masses in questions (thanks again, Monica and Malcolm!)

Other bug fixes

• Persistent Login WordPress plugin broke the Google login button and slowed down the site (thanks, Don!)
• student registration form wasn’t interpreting school expiration dates correctly (thanks, Mary Ann!)
• other “under the hood” improvements

I keep track of every bug or issue that gets reported as well as every new quiz suggestion that’s sent in, so I’m going to continue to do my best to address those throughout the school year. ChemQuiz.net has improved significantly over the past three years thanks to the bug reports and suggestions sent in by teachers and students alike, so please keep sending them in!

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Site licenses for the ChemQuiz.net Dashboard

Thank you to everyone who has already renewed or purchased a new school’s site license for the ChemQuiz.net Dashboard for the 2023-2024 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. Back in the spring, I sent out invoices for this upcoming school year to everyone who had previously purchased a site license, but if you didn’t receive one, please let me know.

Site licenses for the ChemQuiz.net Dashboard from the 2022-2023 school year expired on July 1st, which means that teachers at those schools won’t be able to create new student accounts, classes or assignments. If you plan on renewing for the upcoming school year but need a little extra time for paperwork to go through your local bureaucracy, just drop me a line and I’ll extend your school’s expiration date to September 1st.

If you’d like to purchase a ChemQuiz.net site license for the 2023-2024 school year for just US$50, you can pay through a school purchase order or personal check, or via CashApp, PayPal, Venmo or Zelle at chris@chemquiz.net, or by credit card through Square. Remember, you can also bundle a license for the PhysQuiz.net Dashboard for just US$25 more! Please contact me if you have any questions about site licenses or how to purchase one.

I am fully committed to expanding access to STEM education for students in communities that lack the traditional resources to be successful, so 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!)

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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 The Site Formerly Known as Twitter, on The Site Still Known as Facebook and on Threads 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! Go 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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This upcoming week, my wife and I are traveling to the Green Mountains of Vermont to celebrate our 20th wedding anniversary! We’ve never been to Vermont before, so we’re really looking forward to making the trip before school starts the following week. Maybe we’ll run into Bernie Sanders while we’re there?

Thanks so much for your support over the past three years! Please feel free to get in touch with me via the Contact form or at chris@chemquiz.net if you have any questions, comments, or concerns. Here’s hoping that this upcoming school year is the best one we’ve had in a long time – we could all use it!

-Chris

Hello again! For those of you in the United States and everywhere else that’s almost done with this school year, I hope that everything is wrapping up nicely for each of you. This was my 25th year in education, and it continues to amaze me how each year can be so different from the last.

In this newsletter, I’ve included important information about the following topics:

• Site license renewals due July 1st
• Summer site maintenance
• Coming in Fall 2023 – PhysQuiz.net!
• New quiz features & bug fixes

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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 2023-2024 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 understand their purpose, but I’ve always hated web ads.) 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.

If you take no action, current site licenses for the ChemQuiz.net Dashboard will expire on July 1st, after which you won’t be able to create 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 to September 1st. I’ve taught in three public school districts over my career and each handled purchase orders differently – and they were all in Ohio! – so I understand how convoluted the process can be.

If you currently have a demo account and would like to purchase a site license for the 2023-2024 school year for just US$50, you can pay through a school purchase order or personal check, or via CashApp, PayPal, Venmo or Zelle at chris@chemquiz.net, or by credit card through Square. Please reach out if you have any questions at all about site licenses or how to purchase one!

Site licenses also help me offer the ChemQuiz.net Dashboard for free to public schools in the U.S. with high rates of poverty. I’ve seen firsthand how schools with limited resources have to scrape and scrounge just to be able to teach their subjects (my school just got new Chemistry textbooks for the first time in 21 years, and I’ve personally repaired one-quarter of the desks in our two chem rooms). If ChemQuiz.net can do anything to help a student pass Chemistry in high school, then I figure they’re more likely to go to college and possibly major in science. Who knows! There’s no question our country needs more science literacy.

So far, the free site licenses program has been a success – 96 public schools have taken advantage of this offer, creating 2,500 student accounts and 676 assignments this school year, which have resulted in over 26,000 completed assignments. 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.

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Coming in Fall 2023 – PhysQuiz.net!

Last spring, I planned to spend my spare time during the upcoming school year writing physics practice quizzes for a new website: PhysQuiz.net! I figured I’d be able to “coast” on all of the existing Environmental Science and AP Physics 2 materials I’d developed over the years. Then, two of my science colleagues suddenly resigned – including our department chair – and everything got turned upside down. This ended up being a much more challenging school year than I had expected.

Fortunately, I’ll be teaching physics and computer science next year, so I’ll be able to focus on writing those physics practice quizzes that I meant to get to last year! Also, I’ll have a student helping me who’s going to major in computer science; she’s been learning coding with me since she was in the Kent Girl Coders Club as an 8th grader. The plan is that she’ll help me write physics quizzes this summer so she can develop a portfolio of work for her college applications. Everyone wins!

If you’re interested in news and updates about PhysQuiz.net, please fill out this short form or send me an email at chris@physquiz.net. Once the site is up and running, PhysQuiz.net site licenses will be available at a bundled discount for schools that have already purchased a site license for ChemQuiz.net. More details will be available as we make progress on the new website!

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Summer site maintenance

Each year, ChemQuiz.net has continued to add more schools with more students who generate more quiz results, so it’s necessary to archive older material to keep the website’s database running efficiently. For example, there are currently 158,000 quiz results in one database table just from the past two years! 😱

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 2022-2023 school year (7/1/22 – 6/30/23) will be archived (but not deleted)
• All student accounts created during the 2021-2022 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 back up everything regularly, so I can always restore anything you might need.

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New quiz features & bug fixes

Like many of you, I’ve been especially “teacher tired” this spring! I feel like I’ve had to work harder than ever to keep my students focused and motivated after Spring Break, but they’ve been good sports about it (mostly). As a result, I wasn’t able to find time to write any new quizzes, but I did fix some bugs and add a few new features that I thought would be helpful:

Dashboard

• changed demo account to 30 days with no limit on creating student accounts or assignments
• added the ability to share (create a copy of) an assignment with a colleague at the same school (thanks, Helen!)
• added the ability to quickly restore (unarchive) an assignment from the Assignments page
• apostrophes in text would break “Notes to student” when creating an assignment

All Quizzes

• added the option to not display solution setups after students completed a quiz (thanks, Susan!)

Acid-Base Neutralization Quiz

• answers and problem setups were wrong for problems with multiple hydroxide bases (thanks, Scott & Susan!)

Chemical Equilibrium Quiz

• pressures should use parentheses instead of square brackets in word problems (thanks, Susan!)

Concentrations of Solutions Quiz

• dilution problems sometimes had the same before & after volume or an increase in concentration (thanks, Malcolm!)

Gas Laws Quiz

• correct answers marked as wrong when using “simplified” given values (thanks to my own students for reporting this bug!)
• before & after were sometimes the same when using “simplified” given values
• gas temperatures were often below 200K, which is unlikely

Kinetics & Rate Laws Quiz

• rate constant units were incorrect on some problems involving change in concentration over time (thanks, Debra!)
• rate law answers were being interpreted as scientific notation due to ^ character (thanks, Susan!)
• table header showed “Concentration” instead of “Amount” for problems with moles (thanks again, Susan!)

Stoichiometry & Limiting Reagents Quiz

• answers correctly rounded to the hundredths place were sometimes being marked wrong (thanks, Caitlyn!)

I keep a list of every bug or issue that gets reported as well as every new quiz suggestion, so my plan is to address those once our summer break starts next week. ChemQuiz.net has improved significantly over the past three years thanks to the bug reports and suggestions sent in by teachers and students alike, so please keep sending them in!

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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!
• Opt-in to adding your school to the list of supporters on the About ChemQuiz.net page! Go 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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We only have one more week for semester exams at my school, and then I get to take our Environmental Club to the Ohio Envirothon Competition for the third year in a row! This year’s state competition takes place at Defiance College in Defiance, Ohio, which I’ve driven past but never been to, so I’m looking forward to seeing some new places. If you’re in the U.S. and your state participates in the Envirothon competition, I highly recommend getting involved! In Ohio, the competition is run through our Soil & Water Conservation Districts, so contacting your county’s district may be a good place to start. The kids really learn a lot about regional environmental issues that they don’t normally see in class, and it can be a lot of fun!

Thanks again for all of your support, suggestions and feedback over the past three years! Working on ChemQuiz.net and collaborating with teachers all over the globe has been a deeply fulfilling experience. Please get in touch with me via the Contact form or at chris@chemquiz.net if you have any questions, comments, or concerns. If you’re in the United States, I hope you have a restful and peaceful Memorial Day. Take care, stay safe, and enjoy your summer break!

-Chris

Happy April, everyone! I hope you’re all hanging in there and can see the light at the end of the tunnel. We just finished Spring Break in my district, and it felt great to get a week off to clear my head and wrap up the improvements to ChemQuiz.net I’ve been working on, which I’ve been looking forward to sharing with you.

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NEW Kinetics & Rate Laws Quiz

• determine average and instantaneous reaction rates from a variety of dynamically generated data sets
• write rate laws and determine reaction rate constants
• calculate reaction half-life and changes in concentration over time
• aligns with Next Generation Science Standards Performance Expectation HS-PS1-5: Matter and its Interactions

Thanks to everyone who helped out with resources to help me write this quiz! Right now it uses generic chemical equations (e.g., A + B → C + D), but I’m planning on adding reaction rate constants for real chemical reactions once I’ve scrounged up enough of them to generate enough random questions without repeating. If you have a list of reaction rate constants and are willing to share it with me, please contact me – I’d love to get a copy!

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NEW Solution setups for all quizzes involving calculations

For almost two years now, I’ve wanted to add problem setups for the quizzes that involve calculations, because I’ve personally found that I can learn a mathematical concept a lot faster if I can see how a problem is worked out step by step, so I figured other students would benefit from that feature as well. I wanted to start with the Stoichiometry & Limiting Reagents Quiz because, as I’m sure you know, the conversions can be tricky to visualize for many students. I first tried LaTeX, which is clunky but powerful and has been around forever, but despite my best efforts, I just couldn’t get integrate it consistently with WordPress.

Fortunately, when version 109 was released in January, Google Chrome finally began supporting a mathematical markup language called MathML which is much, much easier to use and integrate into a website like ChemQuiz.net. I started adding problem setups to quizzes in mid-February and finished about three weeks later (I documented the whole process on Twitter with screenshots, if you’re interested). Some of the problem setups were pretty complicated, like this one, which shows the process for solving for the quantity of a substance at equilibrium in the Chemical Equilibrium Quiz:

I hope the problem setups are helpful for you and your students! One caveat: some schools (like mine, for example) keep their ChromeOS devices on the “Long-Term Support” update channel, which lags about six months behind the most recent version. This means that if your students use school-supplied Chrome devices, they may not be able to view the problem setups until July, when Chrome version 109 with MathML support should push out to those devices. I apologize for this temporary inconvenience, but it shouldn’t be long until this feature is available to everyone!

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Quiz alignments with Next Generation Science Standards (NGSS)

I’ve taught science in Ohio for my entire career, and I’ve been evaluated many times, but a relatively new feature of our state’s teacher evaluations is the use of “High Quality Student Data”, or HQSD. For math and English/language arts courses, there are lots of opportunities to collect this data through standardized tests and big name vendors, but for high school science courses like Chemistry, it can be a more time-consuming process.

One of the primary goals of ChemQuiz.net has been to make things easier on everyone – on students trying to learn a new concept, and on teachers trying to focus their energy on helping their students. To that end, I put together an alignment document between the quizzes on ChemQuiz.net and the Performance Expectations of the Next Generation Science Standards (NGSS). For those of you who need to document your usage of standards in your lesson plans, I hope this will make it a little easier and save you some time.

For states that haven’t adopted NGSS, I plan on making more alignment documents this summer, starting with my own state and then focusing on the states that have the most ChemQuiz.net Dashboard subscribers. Eventually I’d like to add standards-based quiz results so that every teacher with a Dashboard account can analyze and download student growth data with minimal extra effort on their part. If you have any thoughts or documentation on your own state standards, please feel free to share them with me!

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New quiz features & bug fixes

While I do my best to keep ChemQuiz.net bug-free, it’s inevitable that some will creep into the thousands of lines of code that make up the site. Since I didn’t send out a March newsletter, this list is a bit longer than usual, especially since I had to update the code for so many quizzes to add the problem setups and figured I might as well fix some bugs while I was digging around in there! Here’s a list of the most recent improvements and fixes to ChemQuiz.net:

Dashboard

• “show individual students” link wasn’t working on “Edit Assignment” form (thanks, Kelly!)
• open/close date was wiped out when saving quiz-specific options (thanks again, Kelly!)
• made “Quiz is active” checkbox more obvious

Acid-Base Equilibrium Quiz

• 15 weak bases were incorrectly listed as acids in the database (thanks, Mary Ann!)

Acid-Base Neutralization Quiz

• acids & bases selected for the quiz weren’t very random

Average Atomic Masses Quiz

• “Load More Problems Like This!” button would crash the quiz

Calorimetry Quiz

• “challenging” word problems were asking for mass even if moles were wanted (thanks, Susan!)

Chemical Equilibrium Quiz

• chemical equilibrium problem wording had multiple issues (thanks again, Mary Ann!)
• quiz would sometimes crash when generating a lot of problems (>10)

Concentrations of Solutions Quiz

• mercury(I) compounds were producing incorrect ions (thanks again, Mary Ann!)
• chemicals selected for solubility quiz weren’t being shuffled properly

Density Quiz

• added an option to use rho (ρ) for density

Hess’s Law Quiz

• some reactions weren’t adding up correctly (thanks again, Mary Ann!)
• entering “0” as a correct answer was being interpreted as “no answer” (thanks again, Susan!)

Lewis Dot Structures Quiz

• generated questions weren’t very random, so I added an array that keeps track of questions that have already been displayed to avoid repeats (thanks, Cynthia!)

Molar Conversions Quiz

• improved question layout

Molecular Geometry & VSEPR Quiz

• grades page is showing incorrect images for valence electrons & domain questions (thanks, Clare!)

Naming Compounds & Calculating Molar Masses Quiz

• added units to presentation mode

Nuclear Reactions Quiz

• “B” was being interpreted as a beta particle instead of boron (thanks, Scott!)
• added 3,361 nuclear decay processes
• fixed a bug that was producing blank problems

Periodic Trends Quiz

• added ion charge to ionic radius questions (thanks, Mike!)

SI Conversions Quiz

• updated prefix for deca- to be “da-” instead of “D-” (thanks, Dorothy!)

Stoichiometry & Limiting Reagents Quiz

• added an option to exclude 1:1 mole ratios (thanks, Drew!)

Thermochemical Equations Quiz

• correct answers were being marked as wrong if rounding due to sig figs was greater than 1% of the calculated answer (thanks again, Scott!)

As always, my sincere thanks go out to everyone who sent in a suggestion or bug report! If at any time 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. Your feedback makes ChemQuiz.net better!

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Looking ahead to the 2023-2024 school year

It’s renewal time! In the next few weeks, I’m going to start sending out invoices for site licenses for the 2023-2024 school year. This time, I’m going to try generating invoices using the 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.

You can purchase a site license now for the 2023-2024 school year for the same price of $US50 through school purchase order or personal check (US only), or via CashApp, PayPal, Venmo or Zelle at chris@chemquiz.net, or you can pay with a credit card through Square. Site licenses help me to pay for web hosting and the software I use to create the site, and they enable me to focus my time outside of school on fixing bugs, adding features and writing new quizzes. I truly appreciate your support!

I understand that situations can change from school year to school 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. The last thing I want to do is pester a fellow educator.

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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!
• Opt-in to adding your school to the list of supporters on the About ChemQuiz.net 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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10 million visits!

On March 22nd, ChemQuiz.net registered its 10 millionth visit since I started the site in the summer of 2020:

It’s a challenge for me to express the deep gratitude I feel toward everyone who helped make this milestone happen, so I’ll keep it simple – from the bottom of my heart, thank you.

Once Spring Break is over, it always feels like we’re in the home stretch for the school year. I’m currently wrapping up my 25th year in public education – a quarter-century! 😱 – and it still amazes me how quickly this time of the year passes. Good luck to any of your students taking the AP Chemistry or IB Chemistry exams! Please don’t hesitate to get in touch with me via the Contact form or at chris@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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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