pH of a solution produced when an aqueous soution of `pH =6` is mixed with an equal volume of an aqueous solution of `pH =3` is about `:`

Options

A. `3.3`
B. `4.3`
C. `4.0`
D. `4.5`

Answer

A

Explanation

pH = 6 means `[H^(+)] = 10^(-6)` M
pH = 3 means `[H^(+)] = 10^(-3) M `
After mixing ,
Total ` [H^(+)] = ((10^(-6) +10^(-3)))/2 = (1.001 xx 10^(-3))/2 `
` = 5.005 xx 10^(-4)`
pH = ` 4- log 5.005 , pH = 3.301 `