Question

Why does HCl gas form a mist of droplets of HCl acid in moist air?
A.HCl gas is less reactive and it is highly soluble in water to form hydrochloric acid
B.HCI gas is very reactive and it is highly soluble in water to form hydrochloric acid
C.HCl gas is very reactive and it is less soluble in water to form hydrochloric acid
D.HCl gas is less reactive and it is less soluble in water to form hydrochloric

Answer 1

Hint: To solve this question, we must first understand the nature of the molecules of both hydrochloric acid and water. Then, we must discuss the type of interactions these molecules have as well as the mechanism behind it.

Complete Step-by-Step Answer:
Before we move forward with the solution of the given question, let us first understand some important basic concepts.
Hydrochloric acid is a colourless gas which is highly reactive in nature. HCl consists of two main constituent atoms, viz. hydrogen and chlorine. The difference between the electronegative characters of these two atoms is very high. Also, the type of bond formed between hydrogen and chlorine is covalent in nature. So, because of the high difference in electronegativity and the covalent character of the bond, there is a formation of dipole in the molecule. This makes it very reactive.
Similar to HCl, water molecules also contain atoms with high difference in electronegativity values. This results in the water molecule acquiring a polar character. And we know that polar molecules are highly reactive towards each other because of dipole – dipole interaction.
Hence, when HCl gas is released in moist air, it reacts with the water molecules in the moist air to form droplets of the compound. Hence, this can be explained by saying that HCI gas is very reactive and it is highly soluble in water to form hydrochloric acid

Hence, Option B is the correct option

Note: Hydrochloric acid or HCl is one of the most commonly produced by – products in chemical reaction. HCl is formed in almost all types of reactions including addition reaction, elimination reactions and even substitution reactions. The hydrochloric acid so formed is often obtained in the gaseous state and many times is allowed to dissipate out of the experimental setup.