$pH$ value of a solution,whose hydronium ion concentration is $6.2 \times 10^{-9} \ mol/L$,is

The degree of dissociation of $0.1 \ M$ acid $HA$ is $5 \%$. The value of $K_c$ of $HA$ is

The ionisation constant of acetic acid is $1.8 \times 10^{-5}$. The concentration at which it will be dissociated to $2\%$,is (in $M$)

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 $3.7 \%$ dissociated. The value of the dissociation constant,$K_a,$ for this acid will be:

Calculate $\alpha$ for $0.1 \ M$ acetic acid $(K_{a} = 1.0 \times 10^{-5})$.

Find the $pOH$ value of $10^{-3} \ M \ NH_4OH$. Given $K_b = 10^{-5}$.