News from ISBerne

In Chemistry, recently, we looked at redox reactions which are chemical reactions that occur when the oxidation state of an element changes depending on the number of electrons it has.

An atom is generally oxidized when it loses electrons or reduced when it gains electrons. So we experimented with a disposable breathalyzer test kit to try a redox reaction that involves the potassium dichromate crystals in the kit and ethanol, which is the common type of alcohol. The potassium dichromate starts as orange/yellow crystals. When they come into contact with ethanol, a redox reaction is created and makes the crystals turn green.

To carry out the test, we did not want to waste it on ourselves because it was just going to end up being a negative alcohol test, obviously! So instead, we collected some vaporized ethanol using a balloon on the top of a conical flask filled with liquid ethanol. Once we collected enough, we pushed it from the balloon and into the bag (to replicate a real-life scenario) so that it could react with the crystals. As we expected, the crystals changed color from orange to green because the potassium dichromate oxidized the ethanol into ethanoic acid, reducing itself from a +6 oxidation state into a +3.

This was a nice, visual way to learn an essential concept of our Chemistry course.