Question

How many litres of water must be added to `1 L` of an aqueous solution of `HCl` with a `pH` of `1` to create an aqueous solution with `pH` of `2`?
A. `9.0 L`
B. `0.1 l`
C. `0.9 l`
D. `2.0 L`

Answer 1

Correct Answer - A
Initial conc. Of HCI solution `(pH=1) =10^(-1) M`
Final conc. Of HCI solution `(pH =2) =10^(-2) M`
`M_(1)V_(1) =M_(2)V_(2)`
`0.1 xx 1L 0.01 xx V_(2)`
`V_(2) =((0.1) xx (1L))/(0.01) =10L`
Volume of water to be added `=(10 -1) =9 L`