Question

Pure methane can be produced by:
(A) Wurtz reaction
(B) Kolbe’s electrolysis method
(C) Soda lime decarboxylation
(D) Reduction with ${H_2}$

Answer 1

Methane is an alkane and it has a chemical formula as $C{H_4}.$ Methane gas is present in abundance on the seafloor. It is a non-toxic gas but it is flammable in nature. This gas is also a greenhouse gas. In the solution, we will understand the formation of pure methane in a detailed manner.

Complete Step By Step Answer:
We know that the chemical formula of methane is $C{H_4}.$ Although methane is present in abundance at the seafloor, a pure form of methane is produced in the laboratory by soda lime decarboxylation.
In this method, the acetic acid salt (such as sodium acetate which is the sodium salt of acetic acid) is heated with soda lime. We know that the chemical formula of soda lime is $NaOH.$ The chemical name of soda lime is Sodium Hydroxide. When it is heated, it leads to a decarboxylation reaction in which carbon dioxide is removed from the compound.
The chemical reaction for the soda lime decarboxylation is given as follows:
$C{H_3}COONa + NaOH \to C{H_4} + N{a_2}C{O_3}$
Hence, in the above reaction we can see that pure methane is produced.
Therefore, the correct option is (C) Soda lime decarboxylation.

Note:
Methane is the simplest alkane which is found on Earth. It is the simplest form of a saturated hydrocarbon. It is an odourless gas which is flammable in nature. It is a non-toxic gas. It has a tetrahedral structure in which the four hydrogens are bonded to the carbon atom with the covalent bonds.