Question

Choose the strongest acid. Acid A, Ka = 2.3 x 10-8 Acid B, Ka = 2.5 x 10-6 Acid C, Ka = 8.3 x 10-7 Acid D, Ka = 1.4 x 10-7

Answer 1

The strength of an acid can be predicted from its acid dissociation constant.

For a hypothetical monoprotic acid HA, the dissociation equilibrium is:

HA ↔ H+ + A-

Ka = [H+][A-]/[HA]

Now, higher the Ka value, greater is the dissociation and stronger is the acid strength

Based on the given examples, Ka is the highest for Acid B= 2.5 * 10⁻⁶. Hence Acid B is the strongest acid.

Ans: Acid B