Question

Which of the following does not make any change in pH when added to $10ml$ dilute $HCl$.

• A. $5ml$ pure water
• B. $20ml$ pure water
• C. $10mlHCl$
• D. Same $20ml$ dilute $HCl$

Answer 1

The correct option is D Same $20ml$ dilute $HCl$

$\text{For the same pH, concentration should remain same. Addition of water causes a change in pH due to change in}$$\text{concentration. When we add to volumes of the same concentration, new concentration remains the same}$

$\text{∴ pH won't change for option D.}$