The solution to Chemical Mystery #13: Bye Bye Blue! is presented. This experiment is useful to demonstrate to students when discussing acid-base indicators, neutralization reactions, or the acidity of carbon dioxide when it dissolves in water.
A simple, but tricky experiment is displayed. Can you figure out how the trick was done?
You are likely aware that diamonds are converted - albeit slowly - to graphite under normal conditions. Thus, diamonds don't last forever, in contrast to the popular advertising slogan. However, did you know that you can use chemistry to prove that diamonds are not forever? It's simpler than you think...
I added an extra step including a follow up Claim, Evidence & Reasoning activity to the familiar whoosh bottle activity.
Looking to change up your titration lab? Citric acid is very common in candy and other foods. Students will be engaged in using titration to find the amount of the acid in Mentos Now or other candy. Student and teacher documents are provided to help you use the activity with your own students.
One 50 minute class period if the instructor prepares the standardized NaOH.
Radioactivity is a topic in chemistry that can be difficult to teach if you are looking for a hands-on, data-driven approach. Safety and cost concerns often prevent students from having an inquiry-based experience with the topic. In this post, I will share how I am able to give my students an authentic lab experience for them to determine there are three types of ionizing radiation without direct instruction.
1 class period
Chad Hustings blogged this past school year about building his own Hoffman apparatus for each group of students. I have been using a Hoffman apparatus that had been purchased by my district before I began teaching there over 20 years ago to demonstrate electrolysis of water, but providing each student group with the ability to perform an electrolysis themselves is a powerful activity. I have used a different version of a homemade Hoffman apparatus, but after reading Chad's blog post, I decided to use a version close to his.
If the Hoffman apparatus is built ahead of time (this takes about 5 minutes for each one if the teacher builds them), then the activity and discussion should take less than a 45 minute period.
My first year teaching chemistry, I was looking for a soap-making lab or activity that I could run in my chemistry class with 25-30 students working at the same time. I usually do this activity right before spring break, as it provides enough time for the soap to harden and cure (high school students are impatient to use their soaps right away, which you should not do with cold process soap). I have used the activity at different points in the curriculum: during intermolecular forces during acids and bases, and during stoichiometry. Although I know teachers who use soap making as a project during their stoichiometry unit, I chose to not emphasize the calculations as it would require more time than I have available. Simply making the soap easily fits in a 45-minute period.
45 minutes to just make the soap. Discussion of key concepts may take another class period.
In an effort to better understand my high school students' knowledge of what is happening during phase changes, heating curve calculations, and the ever popular can crush demo, I run them through a series of activities. First, I ask my students "What Temperature Does Water Boil At?"
1.5 days to do all the activities including lecture on heating curve calculations.
To grasp the concept of oxidation and reduction reactions, I have my high school students write half reactions to show the loss and gain of electrons by the substances being oxidized and reduced. To help with this concept, I developed a quick lab activity involving the reaction between magnesium metal and dilute hydrochloric acid, which in turn led to the students collecting the hydrogen gas and then testing for its presence.