Question

When a 4.00 g sample of KCN is dissolved in water in a calorimeter that has a total heat capacity of 1.94 kJ⋅K−1, the temperature decreases by 0.370 K. Calculate the molar heat of solution of KCN.

Answer 1

Moles of $KCN=\frac{4}{65}=0.0615mol$

Total heat capacity$=n\times C\times∆T$

$1.94=0.0615\times C\times0.370$

$C=85.25\frac{KJ}{mol}$