Question

Zinc is often used to calibrate calorimeters because it undergoes a very sharp phase transition from the solid to the liquid at 419.5°C. Calculate the enthalpy change when 5 g of zinc metal is heated from 100°C to the point where the entire sample is melted. (The heat of fusion for zinc is 112.4 J/g and its specific heat capacity is 0.388 J/g°C.)

Answer 1

q1 = mass Zn x specific heat Zn x (Tf - Ti) where Tf is final T (419.5) and Ti is initial T (100).
q2 = mass Zn x heat of fusion

total = q1 + q2.