Simple chemical tests are described that can indicate the presence of certain metals in coins. A wide variety of chemical concepts are involved. The experiments described are a natural fit for the 2019 National Chemistry Week theme of "Marvelous Metals!"
My district recently provided a professional development session focused on utilizing three dimensional formative assessments in the classroom. The ideas I learned in the session as well an an activity for students to engage in formative assessment are outlined.
Did you know there is a simple test you can do to see if an alkaline battery is fresh or dead? All you need to do is bounce the bottom of a battery onto a hard, flat surface. Guess what causes this difference in bouncing ability between fresh and dead batteries? Chemistry, of course!
This activity is designed to determine the concentration of Vitamin C (ascorbic acid) in a produce protector (in this case, Ball® Fruit Fresh) by an iodometric titration method.
I have tried many different methods to demonstrate or perform displacement reactions over the years with mixed results regarding one particular metal, aluminium. Based upon my experience, the behavior of aluminium in displacement reactions often confuses students.
If rhubarb stem is placed in a solution of permanganate, the purple permanganate ion is reduced to the colorless Mn2+ ion. It is thought that the oxalic acid present in rhubarb causes this reduction. The investigations presented in this post provide evidence that this may not be the whole story...
I found a version of this demonstration online a couple of years ago. I admit, when I first tried it with my class it was mostly for a crowd pleaser to demonstrate the activity series of metals, but I then became very intrigued by the processes occurring. The original source only referenced the “single replacement reaction” between Mg(s) and AgNO3(aq). Therefore, when I saw a grayish product (silver) I was not surprised. However, I was surprised by the white flash and the production of a white product, which were reminiscent of the classic combustion of magnesium demonstration. This led to some research and my conclusions that follow. Read through to the end and you will find a video of the demo.
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.
The chemistry of silver and the process in which silver becomes tarnished is explored. Take a new look at an old JCE Classroom Activity.
A description of a quick and easy lesson that is sure to add some spark into your next lesson on stoichiometry.