Question

Four separate solutions for four sodium salts $NaW$, $NaX$, $NaY$ and $NaZ$ had $pH$ $7.0,9.0,10.0$ and $11.0$ respectively. When each solution was $0.1M$, the strongest acid is:

• A. $HW$
• B. $HX$
• C. $HY$
• D. $HZ$

Answer 1

The correct option is A $HW$

The given salts on hydrolysis give strong base NaOH and acid HA.

Among the given salt solutions, the pH of the solution containing the sodium salt NaW is lowest (7).

This means, the hydrogen ion concentration in this solution is maximum.

This means that the degree of dissociation of HW to give protons is maximum.

Hence, HW is the strongest acid.

OPtion A is correct.