Question

How will you convert the Ethanol to formaldehyde?

Answer 1

For the preparation of formaldehyde from ethanol. ethanol is first converted into ethene by reacting it with $H_{2}S{O}_4$ at 443K.

The ethene so obtained undergoes ozonolysis followed by hydrolysis with Zn and $H_{2}O$ to form formaldehyde as a product.

$\underset{ethanol}{C{H}_{3}C{H}_{2}OH}\underset{443K}{\overset{conc.H_{2}S{O}_4}{\to }}{H}_{2}C=C{H}_2\underset{\left(ii\right)Zn/H_{2}O}{\overset{\left(i\right)O_3}{\to }}\underset{formaldehyde}{2HCHO}+ZnO$