September 2022: New Lab Equipment Quiz and more

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 have kept that knowledge in the forefront of my brain! Teaching Chemistry again also allows me to do fun demos like this:

a test tube containing hydrochloric acid, universal indicator and sodium carbonate produces a pretty rainbow patternIf 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!

5 million visits!

a screenshot of the statistics page from

This past Thursday, September 1st, 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.

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 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 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 a part of leveling the playing field for STEM students around the United States!

New quiz!

a diagram from shows an erlenmeyer flask pouring water into a beaker

*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, or you can fill out the easy-to-use Contact form.

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.

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 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!