Question

Calculate the work done when 2 moles of an ideal gas expands reversibly and isothermally from a volume of 500 ml to a volume of 2 L at 25°C and normal pressure.

Answer 1

Given: n = 2 moles

V_i = 500 ml = 0.5 lit

V_f = 2 lit

T = 25°C = 298 K

w = − 2.303 nRT log `("V"_"f"/"V"_"i")`

w = `-2.303 xx 2 xx 8.314 xx 298 xx log (2/0.5)`

w = − 2.303 × 2 × 8.314 × 298 × log (4)

w = − 2.303 × 2 × 8.314 × 298 × 0.6021

w = − 6871 J

w =− 6.871 kJ