The dissociation of weak electrolyte (a weak base or weak acid) id expressed in terms of Ostwald dilution law. An acid is a substance which furnishes a proton or accepts an electron pair whereas a base is proton acceptor or electron pair donor. Storonger is the acid weaker is its conjugate base. The dissociation constants of an acid `(K_(a))` and its conjugate base are related by `(K_(w)=K_(a)xxK_(b)`, where `K_(w)` is ionic prodcut of water equal to 10-14 at `25^(@)`C. The numerical value of `K_(w)` however increases with temperature. In a solution of an acid or base `[H^(+)][OH^(-)]=10^(14)`.Thus, the `[H^(+)]` in a solution is expressed as : `[H^(+)]=10^(-pH)`and `pH+pOH=14`. Buffer solutions are the solutions which do not show appreciable change in the pH on addition of small amount of acid or base.
`0.16g` of `N_(2)H_(4)(K_(b)=4xx10^(-6))` is dissolved in water and the total volume of solution in made upto 500mL. The percentage of `N_(2)H_(4)` that reacts with water is :

Options

A. `2%`
B. `3%`
C. `1%`
D. `4%`

Answer

a