If the equilibrium constant of $CH_3COOH + H_2O \rightleftharpoons CH_3COO^{-} + H_3O^{+}$ is $1.8 \times 10^{-5}$,what is the equilibrium constant for the reaction $CH_3COOH + OH^{-} \rightleftharpoons CH_3COO^{-} + H_2O$?

$20 \ mL$ of $0.5 \ N \ HCl$ and $35 \ mL$ of $0.1 \ N \ NaOH$ are mixed. The resulting solution will

In which of the following mixed aqueous solutions, $pH = pK_{a}$ at equilibrium?
$(1)$ $100 \ mL$ of $0.1 \ M \ CH_{3}COOH + 100 \ mL$ of $0.1 \ M \ CH_{3}COONa$
$(2)$ $100 \ mL$ of $0.1 \ M \ CH_{3}COOH + 50 \ mL$ of $0.1 \ M \ NaOH$
$(3)$ $100 \ mL$ of $0.1 \ M \ CH_{3}COOH + 100 \ mL$ of $0.1 \ M \ NaOH$
$(4)$ $100 \ mL$ of $0.1 \ M \ CH_{3}COOH + 100 \ mL$ of $0.1 \ M \ NH_{3}$

$A$ solution of sodium bicarbonate in water turns:

At $25\, ^oC$,the dissociation constant of $CH_3COOH$ and $NH_4OH$ in aqueous solution are almost the same. The $pH$ of a $0.01\, N$ $CH_3COOH$ solution is $4.0$ at $25\, ^oC$. The $pH$ of a $0.01\, N$ $NH_4OH$ solution at the same temperature would be:

Which one of the following statements is not true?