A solution of weak acid is diluted by adding an equal volume of water. Which of the following will not change?

Question

A solution of weak acid is diluted by adding an equal volume of water. Which of the following will not change? (A) Strength of the acid (B) The value of [H+]  (C) pH of the solution (D) The degree of dissociation of acid

Tardigrade Admin · Accepted Answer

On adding equal volume of water, the degree of dissociation of acid also increases (according to Ostwalds law), hence, the concentration of H+ ions remains almost constant.

Q. A solution of weak acid is diluted by adding an equal volume of water. Which of the following will not change?

Strength of the acid

The value of $[H^{+}]$

pH of the solution

The degree of dissociation of acid

On adding equal volume of water, the degree of dissociation of acid also increases (according to Ostwalds law), hence, the concentration of $H^{+}$ ions remains almost constant.