February 2023: Discounted site license, progress on kinetics quiz

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? 😂

Discounted site license

Now only US$30 through July 1, 2023!

If you haven’t purchased a site license for the 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:

Screenshot from the Balancing, Identifying & Predicting Chemical Equations Quiz

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, or you can pay with a credit card through Square. Please reach out to me if you have any questions at all!

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!

New quiz features & bug fixes

I hear from teachers and students all the time about suggestions for improving quizzes and about bugs on 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:


  • 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!

Free site licenses for eligible schools

When I first launched 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 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! 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!

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!
  • Add 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.

Thanks again for your continued support and kind words about! 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!