For Day 58, students did some conductivity testing to classify metals and non-metals and ionic compounds and molecular compounds. In the past, I have done this as a demonstration with a large lightbulb conductivity tester. This year, I decided to get creative and sacrifice a strand of LED Christmas lights to make mini-conductivity testers for each group. It’s amazing what you can do with a few 9-volt batteries, aluminum foil, popsicle sticks and Christmas lights.
I set out a variety of metals, non-metals, dissolved ionic compounds and dissolved molecular compounds for students to test. Groups rotated to each lab station to test the conductivities of the various substances.
First we classified metals and non-metals and marked their locations on the periodic table. That then allowed us to see that the dissolved compounds with only non-metals did not conduct electricity and the compounds with metals and non-metals did conduct electricity. With that distinction made, we named these compounds molecular and ionic respectively.