Find the concentration of hydrogen ions in a solution with $pH = 5.4$ in $mol/L$.

Calculate the $[OH^{-}]$ if $pOH$ of a solution is $4.94$.

The ionic product of water at $50^{\circ} C$ is $4 \times 10^{-14}$. The $pH$ and nature of water is :

Calculate the hydrogen ion concentration in the following biological fluids whose $pH$ are given below:
$(a)$ Human muscle-fluid,$6.83$
$(b)$ Human stomach fluid,$1.2$
$(c)$ Human blood,$7.38$
$(d)$ Human saliva,$6.4$

An alcoholic drink has a $pH = 4.7$. What is the $OH^{-}$ ion concentration of this solution? (Given: $K_w = 10^{-14} \ mol^2/L^2$)

The $pH$ of a solution is $9.5$. The solution is