Question

Assertion (A): Increasing order of acidity of hydrogen halides is \[\ce{HF < HCl < HBr < HI}\]

Reason (R): While comparing acids formed by the elements belonging to the same group of periodic table, \[\ce{H - A}\] bond strength is a more important factor in determining acidity of an acid than the polar nature of the bond.

Options

• Both A and R are true and R is the correct explanation of A.

• Both A and R are true but R is not the correct explanation of A.

• A is true but R is false.

• Both A and R are false.

Answer 1

Both A and R are true and R is the correct explanation of A.

Explanation:

As, \[\ce{H - A}\] bond strength is a more important factor in determining acidity than its polar nature. As the size of A increases down the group, \[\ce{H - A}\] bond strength decreases.