In a buffer solution containing equal concentration of $B^{-}$ and $HB,$ the $K_b$ for $B^{-}$ is $10^{-10}.$ The $pH$ of the buffer solution is:

$A$ solution of formic acid is half-neutralized by the addition of a $KOH$ solution. If $K_a (HCOOH) = 2 \times 10^{-4}$,what is the $pH$ of the solution? (Given: $\log 2 = 0.3010$)

Which one of the following pairs of solutions is not an acidic buffer?

The addition of small amounts of either acid or base to a buffer solution causes only small changes in $pH$ because the buffer solution

$50 \, mL$ of $2 \, N$ acetic acid mixed with $10 \, mL$ of $1 \, N$ sodium acetate solution will have an approximate $pH$ of $(K_a = 10^{-5})$

What will be the change in $pH$ by adding $0.1 \ M \ NH_4Cl$ to $0.1 \ M \ NH_4OH$ (weak base) solution? (Given: $K_b$ of $NH_4OH = 1.77 \times 10^{-5}$)