You compress 0.5 moles of a gas at constant pressure from 4 liters to 1 liter while 2625 J of heat is removed, the temperature drops by 180.4 K, and Eth drops by 1875 J. How much work energy is added to the gas?

The work energy added to the gas is

W = -72.48472 kJ

Explanation:

For constant pressure process

Work is given W = p×

However dH = m× = 1875 J

For mass m, dQ = 2625 J

That is m×1875 = 2625 or m = 2625/1875 = 1.4 kg

Therefore work doneper unit mass of gas is -W = p×(v₂ - v₁)

but pv = RT therefore work done per unit mass = -R×(T₂ - T₁) = -R×ΔT and

ΔT = 180.4K

Work done = -1.4×0.287×180.4 = -72.48472 kJ