The principle of conductometric titration is based on the fact that during the titration one of the ions is replaced by other and invariably these two ions differ in the ionic conductivity.

In the conductometric titration of $0.05 \mathrm{M}$ ${\mathrm{H}}_2{\mathrm{SO}}_4$ with $0.1 \mathrm{M} {\mathrm{NH}}_4\mathrm{OH}$, initially the fast moving ${\mathrm{H}}^{+}$ ion get neutralised as ${\mathrm{H}}_2\mathrm{O}$ and is replaced by slow moving ${\mathrm{NH}}_4^{+}$ ion up to neutralisation point. After neutralisation point, weak electrolyte ${\mathrm{NH}}_4\mathrm{OH}$ is added gradually, which do not affect the conductance.