Question

Which of the following elements is extracted commercially by the electrolysis of an aqueous solution of its compound?
A. Chlorine
B. Bromine
C. Aluminium
D. Calcium

Answer 1

Hint: Generally halogens are obtained by the electrolysis of an aqueous solution of its compound. The compound is generally the salt of the halogen like sodium chloride, sodium fluoride etc.

Complete Step by Step Answer:
The aqueous solution of the salt of chloride that is sodium chloride on electrolysis gives a strong base sodium hydroxide along with the formation of hydrogen gas and chlorine gas. The reaction can be given as follows
\[2NaCl+2{{H}_{2}}O\to 2NaOH+{{H}_{2}}+C{{l}_{2}}\]
Thus in this reaction two moles of salt of chlorine that is sodium chloride undergo hydrolysis in aqueous state to produce two moles of a strong base that is sodium hydroxide along with the formation of one mole of hydrogen gas and one mole of chlorine gas. Thus we can write that chlorine gas can be obtained by the electrolysis of sodium chloride.
Aluminium and calcium are alkaline earth metals so, they are obtained easily by the fused electrolysis method.
Thus the correct option is A.

Note: Sodium chloride is an ionic compound. In addition to water it breaks down into ions. This ions help in conducting electricity.