you need
  • - a device for the production of ethylene;
  • - concentrated sulfuric acid;
  • - ethyl alcohol;
  • - bromine water or potassium permanganate;
  • - heater.
Ethyl alcohol is a colorless liquid with a characteristic odor of alcohol.It is used to produce ethanol and ethylene.This experience is considered to be accessible and safe enough for even the school chemistry course.Ethylene - a gaseous substance which is not visually detect possible.However, its presence proves the qualitative response to unsaturated hydrocarbons.
For the experiment, take a test tube with a stopper and a gas outlet tube.Attach the device to produce ethylene and laboratory tripod.Fill the tube with
2-3 ml of ethyl alcohol.Very carefully add to the concentrated sulfuric acid, which must be taken in an amount of 2 times the volume of alcohol (ie 6-9 ml).
So how will need to be heated, then the resulting mixture is sure to add a little cleaner (pre-calcined and purified from impurities) of sand.It will prevent the mixture from the discharge from the vessel.Close the vial stopper and begin to heat it.Concentrated sulfuric acid has a dehydrating property that allows it to "take away" the water.As a result of the dehydration reaction occurs, i.e. elimination of water.As a result, formed gaseous - ethylene .
Since it is impossible to see, then to confirm the reaction carried out experiments.To do this, skip the flow of ethylene and through bromine water having a brown color.Bromine water discoloration will occur, indicating that the halogenation reaction occurred (in particular bromination) and ethylene.This reaction is the quality in the unsaturated hydrocarbons, namely ethylene .
Since bromine water - very toxic compound, it can be replaced by potassium permanganate (potassium permanganate vulgaris).Prepare a dilute solution of potassium permanganate, acidified with sulfuric acid it and pass through it ethylene .There will be discoloration of the solution, which also indicates the presence of ethylene well, which was formed in the first experiment.