Chemical Mystery #8: Go Blue!
Addition of a white solid to a green solution causes the solution to separate into some truly beautiful colors...
Addition of a white solid to a green solution causes the solution to separate into some truly beautiful colors...
Is it possible to use materials found in high school chemistry labs to extract and subsequently detect cocaine on dollar bills? Let me know what you think after reading this blog post!
For my students and me, the AP Chemistry exam does not mark the end of the school year. Once the AP exam is over, my students are exhausted but our class continues to meet for three more weeks. Each year we complete a qualitative analysis lab, but this year we finished earlier than I anticipated. For the first time all year, I have the luxury of time.
Organic chemistry was when I fell in love with chemistry. Also known as Chem 210 at the University of Michigan, it was the first time I actually started to connect what was going on at the nanoscopic level to the macroscopic world. Since then, I’ve been hooked.
First, I had my students examine the conductivity of a puddle of water the size of a nickel. They checked for conductivity. Then they took a very small amount of sodium carbonate and a fresh puddle of water and pushed in a few crystals from the side. You can still see the crystals in the water but it tested positive for conductivity. They had to explain this. They did the same with a fresh puddle of water and a few crystals of copper (II) sulfate. Again, it tested positive for conductivity but they could still see the blue crystal. Finally, they started again with another fresh puddle of water, pushed a few crystals of sodium carbonate on one side and on the opposite side they pushed in a few crystals of copper (II) sulfate. After waiting five minutes, a solid dull blue precipitate formed in the middle. Also, the drop tested positive for conductivity.
An advantage to teaching on the trimester schedule allows me the opportunity to teach the same course again roughly twelve weeks later. So after grading my 2nd trimester students’ Chemistry B final exams, I was able to evaluate certain topics that caused my students problems, reflect on my teaching, and then determine how I was going to better prepare my students in the 3rd trimester chemistry B class.
This is a Chemical Reactions lab that I modified to meet NGSS guidelines.
My local chapter of the American Chemical Society sponsors an annual event at a local mall called “Chemistry at the Mall”. The event is in celebration of National Chemistry Week. This year’s theme is “The Sweet Side of Chemistry – Candy”. I advise an ACS ChemClub and we hosted a table at “Chemistry at the Mall”. Ten student members worked shifts from 11am – 4pm. This was a great way to get involved with my local chapter and meet some other members. My students had a great time providing outreach and introducing young children to chemistry.
We are encouraged to use modelling these days and I have some activities to share along with some videos that might help you in the process.
This simple, yet interesting experiment that was first described by Elizabeth Sumner Walter in 2001. She merely had students pour water into a dish containing some Gobstoppers candies.