Question

Calculate the number of kJ of heat necessary to raise the temperature of 60.0 g of aluminium from 35°C to 55°C. Molar heat capacity of Al is 24 J mol^-1 K^-1.

Answer 1

The expression of heat (q) is written as follows :
q = m.c. ∆T ….(i)
Where, c = molar heat capacity = 24 J mol^-1 K^-1
m = mass of substance = 60 g = 60/27 mol
∆T = change in temperature = 20°C (35°C to 55°C)
Substituting the values in equation (i), we get
q = m.c.∆T
q = (60/27) × 24 × 20
= 1066.7 J q
= 1.07 kJ