Ionic product of water at $310 \,K$ is $2.7 \times 10^{-14}$. What is the $\mathrm{pH}$ of neutral water at this temperature?

Vedclass pdf generator app on play store
Vedclass iOS app on app store

Ionic product,  $K_{w}=\left[ H ^{+}\right]\left[ OH ^{-}\right]$

Let $\left[ H ^{+}\right]=x$

Since $\left[ H ^{+}\right]=\left[ OH ^{-}\right], K_{ w }=x^{2}$

$\Rightarrow K_{ w }$ at $310 \,K$ is $2.7 \times 10^{-14}$.

$\therefore 2.7 \times 10^{-14}=x^{2}$

$\Rightarrow x=1.64 \times 10^{-7}$

$\Rightarrow\left[ H ^{+}\right]=1.64 \times 10^{-7}$

$\Rightarrow pH =-\log \left[ H ^{+}\right]$

$=-\log \left[1.64 \times 10^{-7}\right]$

$=6.78$

Hence, the $pH$ of neutral water is $6.78$

Similar Questions

The first and second dissociation constants of an acid $H_2A$ are $1.0 \times 10^{-5}$ and $5.0 \times 10^{-10}$ respectively. The overall dissociation constant of the acid will be

  • [AIEEE 2007]

A weak acid is $ 0.1\% $ ionised in $0.1\, M $ solution. Its $pH$  is

${K_{C{H_3}COOH}} = 1.9 \times {10^{ - 5}}$. Calculate $pH$ at end point in titration of $0.1$ $M$ $C{H_3}COOH$ and $0.1$ $M$ $NaOH$.

Assuming that the degree of hydrolysis is small, the $pH$ of $0.1\, M$ solution of sodium acetate $(K_a\, = 1.0\times10^{- 5})$ will be

  • [JEE MAIN 2014]

Derive the equation of ionization constants ${K_a}$ of weak acids $HX$.