Question

A litre solution of pH = 1 diluted upto 10 times. what volume of a solution with pH=2 is to be added in diluted solution so that final pH remains '2 '.

• A. 1 litre
• B. 10 litre
• C. 100 litre
• D. 25 litre

Answer 1

Answer: (A), (B), (C), (D)

The correct options are
A 1 litre
B 10 litre
C 100 litre
D 25 litre

After dilution $\left[H^{+}\right]={10}^{-2}\Rightarrow pH$ = $2$

Let V litre solution of pH = 2 is added in original solution so that pH remains fixed.

$\therefore \left[H^{+}\right]=\frac{{10}^{-2}\times 10+V\times {10}^{-2}}{10+V}={10}^{-2}$

This result is independent of volume taken.