Question

State one relevant observation for the following:

When the gaseous product obtained by the dehydration of ethyl alcohol is passed through bromine water.

Answer 1

Explanation:

• The gaseous product obtained by the dehydration of Ethanol $\left({\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}\right)$ is Ethene $\left({\mathrm{C}}_2{\mathrm{H}}_4\right)$.
• When Ethene is passed through bromine water it turns colorless.
• Reaction of Ethanol with Bromine water is as follows.

$\underset{\mathrm{Ethanol}}{{\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}\left(\mathrm{l}\right)}+\underset{\mathrm{Bromine}\mathrm{water}}{{\mathrm{Br}}_2\mathrm{water}\left(\mathrm{l}\right)}\to \underset{\mathrm{Ethene}}{{\mathrm{C}}_2{\mathrm{H}}_4(\mathrm{g}})$

• Reaction of Ethene with bromine water is as follows.

$\underset{\mathrm{Ethene}}{{\mathrm{C}}_2{\mathrm{H}}_4\left(\mathrm{g}\right)}+\underset{\mathrm{Bromine}\mathrm{water}}{{\mathrm{Br}}_2\mathrm{water}\left(\mathrm{l}\right)}\to \underset{1,2\mathrm{dibromo}\mathrm{ethane}\left(\mathrm{Colorless}\right)}{\mathrm{Br}-{\mathrm{CH}}_2-{\mathrm{CH}}_2-\mathrm{Br}\left(\mathrm{l}\right)}$