Question

Which of the following will produce a buffer sollution when mixed in equal volumes ?
A. `0.1" mol dm"^(-3)NH_(4)OHand0.1" mol dm"^(-3)HCl`
B. `0.05" mol dm"^(-3)NH_(4)OHand0.1" mol dm"^(-3)HCl`
C. `0.1"mol dm"^(-3)NH_(4)OHand0.05" mol dm"^(-3)HCl`
D. `0.1"mol dm"^(-3)CH_(3)COONaand0.1" mol dm"^(-3)NaOH`

Answer 1

Correct Answer - C
In 0.1 mol `dm^(-3)NH_(4)OH and 0.05` mol `dm^(-3)` HCl, total amount of HCl reacts with `NH_(4)OH` to form `NH_(4)Cl` and some `NH_(4)OH` will be left unreacted. Thus, the resultant solution contains `NH_(4)Cl and NH_(4)OH` which will produce a buffer solution.