Laboratory preparation of trichloromethane

Peparation of Chloroform From carbon tetrachloride

Now-a-days, chloroform is obtained on a large scale by the reduction of carbon tetrachloride with iron fillings and water.

Fe / H2o
CCI4 + 2H ———→ CHCI3 + HCI

This chloroform is not pure and used mainly as a solvent.

(iii) Pure Chloroform is obtained by distilling chloral hydrate with concentrated sodium hydroxide solution.

CCI3 CH (OH)2 + NaOH ——→ CHCI3 + HCOONa + H2O
Chloral hydrate

Chloral hydrate is a stable compound inspite of the fact that -OH two groups are

linked to the same carbon atom. This is due to the fact that

intramolecular hydrogen bonding exists in the molecule between chlorine and

hydrogen atom of -OH group.

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