Question

Formation of ${\text{HCl}}$ from its elements takes place in the presence of sunlight.
A) True
B) False

Answer 1

Hint: For the formation of hydrochloric acid there is a reaction between the hydrogen gas and the chlorine gas and this reaction happens with the rapid reaction of these elements. One can think about the reaction initiation step where there is a need for energy to start the reaction and which can provide sufficient energy for this reaction.

Complete step by step answer:
1) First of all we will discuss the reaction of the formation of hydrochloric acid and decide if it can happen in presence of sunlight or another medium.
2) The process of formation of hydrochloric acid is done by the reaction of hydrogen gas with the chlorine gas which gives the product as hydrochloric acid in gaseous form. The general reaction is as below,
${H_{2(g)}} + C{l_{2(g)}}\xrightarrow{{{\text{UV Light(sunlight)}}}}2HC{l_{(g)}}$
3) Now to react to the gases of hydrogen $({H_2})$ and chlorine $(C{l_2})$ there is a need for the sunlight that is UV light which initiates the reaction and gives the products as the gaseous hydrochloric acid. This reaction is an exothermic reaction which means there is a formation of heat in this reaction that means heat is evolved during this reaction procedure.
4) The hydrochloric acid formed is in gaseous form and it is converted into liquid form by deionizing it in the water solvent which makes the solution acidic.
Therefore, the given statement in question which is the formation of ${\text{HCl}}$ from its elements takes place in the presence of sunlight is true which shows option A as the correct choice.

Note:
The formation of the hydrochloric acid takes place in the presence of diffused sunlight and not in direct sunlight. In the presence of direct sunlight, an explosive reaction happens and in the case of no sunlight, there is no reaction.