The dissociation of water at $25 \, ^\circ C$ is $1.9 \times 10^{-7} \%$ and the density of water is $1.0 \, g/cm^3$. The ionisation constant of water is

At $25^{\circ}C$,the dissociation constants of acetic acid and $HCN$ are $1.5 \times 10^{-5}$ and $4.5 \times 10^{-10}$ respectively. What is the equilibrium constant for the following reaction? $(CN^- + CH_3COOH \rightleftharpoons HCN + CH_3COO^-)$

When $20 \, mL$ of $0.25 \, N$ strong acid and $30 \, mL$ of $0.2 \, N$ strong base are mixed,the resulting solution will be.......

Arrange the following resultant mixtures in increasing order of their pH values:
$A$. $10 \text{ mL } 0.2 \text{ M } Ca(OH)_2 + 25 \text{ mL } 0.1 \text{ M } HCl$
$B$. $10 \text{ mL } 0.01 \text{ M } H_2SO_4 + 10 \text{ mL } 0.01 \text{ M } Ca(OH)_2$
$C$. $10 \text{ mL } 0.1 \text{ M } H_2SO_4 + 10 \text{ mL } 0.1 \text{ M } KOH$
Choose the correct answer from the options given below:

$0.01 \ M \ HA(aq.)$ is $2 \%$ ionized,$[OH^{-}]$ of solution is :-

Arrange the following $1 \ L$ aqueous solutions of equal concentration in increasing order of their $pH$:
$CH_3COONa, KI, NH_4Cl, HNO_3$