Question

Ethanol is prepared industrially by

• A. Hydration of ethylene
• B. Fermentation of sugars
• C. Both the above
• D. None of these

Answer 1

Answer: (C)

Hydration of ethene
$CH_{2} = CH_{2}+ \overset{+}{H}HS\overset{-}{O_{4}} \to CH_{3} - CH_{2}- HSO_{4}$
$CH_{3} - CH_{2}HSO_{4} \xrightarrow[{Boil}]{{H_{2}O}}CH_{3}-CH_{2}-OH+H_{2}SO_{4}$
Fermentation of sugars:
$C_{12}H_{22}O_{11}+H_{2}O \xrightarrow{{\text{Invertase}}} \underset{\text{Glucose}}{{C_{6}H_{12}O_{6}}}+\underset{\text{Fructose}}{{C_{6}H_{12}O_{6}}}$
$\underset{\text{Glucose or Fructose}}{{C_{6}H_{12}O_{6}}} \xrightarrow{{\text{Zymase}} }2C_{2}H_{5}OH+2CO_{2}$