When $CO_2$ dissolves in water, the following equilibrium is established

$C{O_2} + 2{H_2}O\, \rightleftharpoons {H_3}{O^ + } + HCO_3^ - $

for which the equilibrium constant is $3.8 \times 10^{-7}$ and $pH = 6.0$. The ratio of  $[HCO_3^- ]$ to $[CO_2]$ would be :-

Accumulation of lactic acid $(HC_3H_5O_3),$ a monobasic acid in tissues leads to pain and a feeling of fatigue. In a $0.10\, M$ aqueous solution, lactic acid is $3.7\%$ dissociates. The value of dissociation constant, $K_a,$ for this acid will be

The ionization constant of $HF$, $HCOOH$ and $HCN$ at $298\, K$ are $6.8 \times 10^{-4}, 1.8 \times 10^{-4}$ and  $4.8 \times 10^{-9}$ respectively. Calculate the ionization constants of the corresponding conjugate base.

A solution of sodium borate has a $pH$ of approximately

The percentage of pyridine $(C_5H_5N)$ that forms pyridinium ion $(C_5H_5N^+H)$ in a $0.10\, M$ aqueous pyridine solution ($K_b$ for $C_5H_5N = 1.7 \times 10^{-9}$) is

The $pH$ of $0.004 \,M$ hydrazine solution is $9.7 .$ Calculate its ionization constant $K_{ b }$ and $pK _{ b }$