chemistry question

Question

A sample of gas occupies a volume of 69.9 mL. As it expands, it does 134.9 J of work on its surroundings at a constant pressure of 783 Torr. What is the final volume of the gas?

Answer 1

The work done is pressure times volume change, W = P ΔV, where P must be in units of Pascals and volume in cubic meters. P = 783 torr * (1.013 x 10⁵ Pa / 760 torr) = 1.044 x 10⁵ Pa. ΔV = W/P = (134.9 J) / (1.044 x 10⁵ Pa) = 1.293 x 10^-3 m³ = 1.293 L = 1,293 mL. So new volume is 69.9 mL + 1,293 mL = 1,362 mL.