I set up a zinc-copper elctrochemical cell by placing both electrodes in lemon juice to test the ability of lemon juice to conduct a current. I used a voltmeter and attached each lead to one of the metal electrodes. What I observed was that the voltage over time given on the voltmeter began to...
The black snake reaction is pretty dramatic too. I have done this for my students and they love it. You have to do it in a fume hood, with goggles, gloves and lab coat because the products are nasty -- moist, hot unreacted sulfuric acid and SO2. It's a dehydration reaction of sugar using conc...