April 2023: new kinetics & rate laws quiz and more!

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 I’ve been working on, which I’ve been looking forward to sharing with you.

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!

NEW Solution setups for all quizzes involving calculations

Stoichiometry & Limiting Reagents Quiz example problem setupFor 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 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:

Chemical Equilibrium Quiz example problem setupI 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!

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 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 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 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!

New quiz features & bug fixes

While I do my best to keep 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


  • “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 Your feedback makes better!

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, 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 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.

Help me share with the world!

If you like using, 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 and encourage them to try out the Dashboard!
  • Opt-in to adding your school to the list of supporters on the About page by going to the Dashboard, click on “Your Info” in the top menu bar, check the box next to “Display School on“, and click the “Update Your Info” button.

10 million visits!

On March 22nd, 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