Ammonia gas dissolves in water to give $NH_4OH$. In this reaction,water acts as:

In the equilibrium $CH_3COOH + HF \rightleftharpoons CH_3COOH_2^+ + F^{-}$,which of the following statements is correct?

Given the following $K_a$ values,determine which species is the strongest base: $HSO_4^- = 1.2 \times 10^{-2}$,$H_2PO_4^- = 6.3 \times 10^{-8}$,$HCO_3^- = 4.7 \times 10^{-11}$.

The ionization constants of two bases $AOH$ and $BOH$ are $K_{b1}$ and $K_{b2}$ respectively. Their relationship is $pK_{b1} < pK_{b2}$. Which of the following does not represent the base with the highest $pH$?

The conjugate base of a strong acid is a

The conjugate acid of $NH_2^-$ is