At `25^(@)C` molar conductance of `0.1` molar aqueous solution of ammonium hydroxide is `9.54 ohm^(-1) cm^(2) mol^(-1)` and at infinte dilution its molar conductance is `238 ohm^(-1) cm^(2) mol^(-1)` The degree of ionisation of ammonium hydroxide at the same concentration and termperature is

Options

A. `40.800 %`
B. `2.080 %`
C. `20.800 %`
D. `4.008%`

Answer

D

Explanation

`% alpha = lambda^( c)/lambda^(infty) xx 100 = 9.54/238 xx 100 = 4.008 %`