Question

What amount of heat must be supplied to 2.0 × 10^–2 kg of nitrogen (at room temperature) to raise its temperature by 45 °C at constant pressure? (Molecular mass of N₂ = 28; R = 8.3 J mol^–1 K^–1.)

Answer 1

Mass of nitrogen, m = 2.0 × 10^–2 kg = 20 g

Rise in temperature, ΔT = 45°C

Molecular mass of N₂, M = 28

Universal gas constant, R = 8.3 J mol^–1 K^–1

Number of moles,

Molar specific heat at constant pressure for nitrogen,

The total amount of heat to be supplied is given by the relation:

ΔQ = nC_P ΔT

= 0.714 × 29.05 × 45

= 933.38 J

Therefore, the amount of heat to be supplied is 933.38 J.