Laboratory Preparation of Diethyl ether (Ethoxyethane)

Class XII - Chemistry

HSEB NOTES

 Theory :-

Diethyl ether is prepared in the laboratory by the reactin of ethanol with conc. H₂SO₄ at 140^o C.

The reaction takes place in the following steps :-

a.       Ethyl alcohol reacts with conc. H₂SO₄ at 110^o C to give ethyl hydrogen sulphate.

 b.      Ethyl hydrogen sulphate again reacts with ethanol to give diethyl ether at  140^o C.

Procedure :-

100 ml of ethyl alcohol is taken in a R.B. flask and 50 ml of Conc. H₂SO₄ is added slowly stirring it. And this mixture is heated at 140^o C over sand bath. The ether produced is condensed in the condenser and received in receiver over ice water.

Purification :-

The diethyl ether may be contaminated with the impurities of Conc. H₂SO₄ , ethanol, ethyl hydrogen sulphate etc. Hence, the impure ether is kept in a separating funnel in which NaOH is added. The layer of impurities and ether and water are separated. The ether is then passed through anhydrous calcium chloride.