\( 17.0 \, \text{g} \) of \( \text{NH}_3 \) completely vapourises at \( -33.42^\circ \text{C} \) and \( 1 \, \text{bar} \) pressure and the enthalpy change in the process is \( 23.4 \, \text{kJ mol}^{-1} \). The enthalpy change for the vapourisation of \( 85 \, \text{g} \) of \( \text{NH}_3 \) under the same conditions is ________ \( \text{kJ} \).
