2023 HydrocarbonsPreparation of Alkanes – Decarboxylation Medium Question 10 of 75 in Hydrocarbons

Weight (g) of two moles of the organic compound, which is obtained by heating sodium ethanoate with sodium hydroxide in presence of calcium oxide is:

A 18
B 16
C 32
D 30

The answer is C.

Solution

Soda-lime decarboxylation gives methane (molar mass 16), so two moles weigh 32 g.

Sodium ethanoate is $CH_3COONa$ and the given process is soda-lime decarboxylation. $CH_3COONa+NaOH\xrightarrow{CaO}CH_4+Na_2CO_3$ Methane is obtained having molar mass 16. Two moles would be 32 g.

Concept soda-lime decarboxylation gives methane

Hydrocarbons in past papers

75 questions from this chapter have appeared across 26 exam years.