Question

1. Calculate the initial volume of a gas if it is compressed to a final volume of 1.4 L at a constant pressure of 2.7 atm and results in 457.J of work.

Answer 1

by defintion

work = -pdV

work = - p (Vf - Vi)

given

pressure (p) = 2.7 atm = 2.7 atm x (101325 Pa / 1 atm ) = 273578 Pa

now

Vf = 1.4 L = 1.4 L x ( 10-3 m3 / 1 L ) = 1.4 x 10-3 m3

plug in the values

457 J = -273578 Pa x ( (1.4 x 10-3 )- Vi ) m3

Vi = 3.07 x 10-3 m3

Vi = 3.07 x 10-3 m3 x ( 1000 L / 1 m3)

Vi = 3.07 L

so

the initial volume of the gas is 3.07 L