Question

Will it be right to say that an acid with more protocity or basicity will be more stronger acid?

Answer 1

The strength of an acid refers to its ability or tendency to lose a proton (H+). A strong acidis one that completely ionizes (dissociates) in a solution (provided there is sufficient solvent). In water, one mole of a strong acid HA dissolves yielding one mole of H+ (as hydronium ion H3O+) and one mole of the conjugate base, A−. Essentially, none of the non-ionized acid HA remains. Examples of strong acids are hydrochloric acid (HCl), hydroiodic acid (HI), hydrobromic acid (HBr), perchloric acid (HClO4), nitric acid (HNO3) and sulfuric acid (H2SO4). In aqueous solution, each of these essentially ionizes 100%.

In contrast, a weak acid only partially dissociates. Examples in water include carbonic acid (H2CO3) and acetic acid(CH3COOH). At equilibrium, both the acid and the conjugate base are present in solution.

Stronger acids have a larger acid dissociation constant (Ka) and a smaller logarithmic constant (pKa = −log Ka) than weaker acids. The stronger an acid is, the more easily it loses a proton, H+. Two key factors that contribute to the ease of deprotonation are the polarity of the H—A bond and the size of atom A, which determines the strength of the H—A bond. Acid strengths also depend on the stability of the conjugate base.