The oxidisation of ethanol

Debbie Warner

Introduction

Ethanol is a primary alcohol and can be oxidised to produce either an aldhyde or a carboxylic acid.

CH CH OH + [O] → CH CHO +H O

CH CH OH + 2[O] → CH COOH + H O

The purpose of this experiment is to oxidise ethanol and then test the product to determine whether it has been oxidised to ethanol or oxidised to ethanoic acid.

Safety

As with all experiments, it is essential to perform procedures safely. In this experiment ethanol, which is highly flammable is being heated so goggles should be worn and hair tied back, a stopper should be used to stop the ethanol from boiling over so that there in no chance of the ethanol being exposed to the naked flame. When using chemicals such as sodium dichromate, which stains, utmost care must be taken to ensure there are no spillages of the chemical directly or in a solution, gloves should also be worn when handling this chemical. Gloves should also be worn when handling sulphuric acid, which is highly corrosive. Also cuts and broken skin should be covered, and hands should be washed after handling any chemicals. If contact with skin does occur it should be washed with cold water immediately.

Observations

During distillation

As the mixture containing ethanol was added slowly into the pear shaped flask, the mixture in the flask first started to turn a green colour, after about 15 seconds, and as more of the mixture containing ethanol was added the colour of the mixture became continually darker. The mixture continued to bubble as the mixture containing ethanol was added, showing the mixture was still boiling. As this bubbling became fiercer, (after about 1 minute) clouds of gas began to form and travel down the tube to the conical flask in iced water, as this continued and ...