Question

How would you convert;
a) Ethanol into ethene?
b) Propanol into propanoic acid?
Name the process in each case and write the equations of the reactions involved.

Answer 1

Hint: Ethanol can be converted to ethene by dehydration of ethanol. In dehydration an ethanol is heating at high temperature in the presence of concentrated sulphuric acid. The phosphoric acid can also be used instead of sulphuric acid.

Complete step by step solution:
Ethanol is an organic compound with the formula $ {{C}_{2}}{{H}_{5}}OH $ .It has a higher boiling point than ethane or another hydrocarbon such as alkane, alkyne with the same number of carbon atoms. Ethanol can directly convert to ethene by heating the ethanol in the presence of concentrated sulphuric acid. Ethanol removed water molecules from it. This process is called dehydration. The reaction of dehydration is,
 $ {{C}_{2}}{{H}_{5}}OH\to C{{H}_{2}}C{{H}_{2}}+{{H}_{2}}O $
Mechanism of the reaction is, the mechanism of the acid dehydration has three steps. First step is the protonation of the oxygen atom of the $ -OH $ group. Second step is the removal of water molecules to form carbonium anion and the last step is the deprotonation to form carbon double bonds.
Dehydration: conversion of ethanol into ethene.
 $ C{{H}_{3}}-C{{H}_{2}}OH\xrightarrow[\left( Dehydration \right)]{conc.~{{H}_{2}}S{{O}_{4}};~{{170}^{\circ }}C}C{{H}_{2}}=C{{H}_{2}}+{{H}_{2}}O $
Oxidation: conversion of propanol to propanoic acid.
 $ C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}OH+2\left[ O \right]\xrightarrow[or\centerdot acidified~{{K}_{2}}C{{r}_{2}}{{O}_{7}}]{Alkaline~KMn{{O}_{4}};~Heat}C{{H}_{3}}C{{H}_{2}}COOH+{{H}_{2}}O $ .

Note:
Ethanol is an organic molecule which contains functional $ -OH $ . So, it is a class of alcohol. The molar mass of ethanol. The melting and boiling point of ethanol is and It is used as Antiseptic, Addition in petrol, Medicine, Solvent and alcoholic drink. Ethene: Ethene is an organic compound which consists of two carbon double bonds.