Thunderstorm in a test-tube – a hazardous reaction – small scale only



WARNING: This should only be attempted by an experienced chemist. The experiment is extremely dangerous as it involves concentrated sulfuric acid which is CORROSIVE and ethanol which is FLAMMABLE. There is a small chance of an explosion due the the manganese oxides produced in the presence of ethanol vapour and oxygen gas. Face shields, goggles, thick fire proof gloves and a safety screen should be used. A fire extinguisher should be available. Follow your laboratory safety procedures and carry out your own risk assessment before doing the experiment.

We carried out the experiment on a very small scale using approximately 1ml ethanol and less than 1 ml of concentrated sulfuric acid. We used 4 small crystals of potassium manganate (VII).

Procedure:
1. Place approximately 1 ml ethanol in a test-tube.
2. Using a glass Pasteur pipette, introduce just less than 1 ml of concentrated sulfuric acid into the bottom of the tube.
3. Add four small crystals of potassium manganate (VII)

Observe behind a safety screen.

VERY IMPORTANT: Allow the reaction to go to completion (at least 10 minutes) before disposing of down the sink with plenty of cold running water.

See:

and

https://people.bu.edu/straub/courses/demomaster/storm.html

for more details.


Post time: Apr-04-2017