Question

Consider as a system the gas in a vertical cylinder; the cylinder is fitted with a piston on which a number of small weights are placed. The initial pressure is 200 kPa, and the initial volume of the gas is 0.04 m3 . (a) Let a Bunsen burner be placed under the cylinder, and let the volume of the gas increase to 0.1 m3 while the pressure remains constant. Calculate the work done by the system during this process. (b) Consider the same system and initial conditions, but at the same time that the Bunsen burner is under the cylinder and the piston is rising, remove weights from the piston at a rate such that, during the process, the temperature of the gas remains co

Answer 1

Step-by-step explanation:

a ) At constant pressure , work done = P x Δ V

= 200 x 10³ x ( .1 - .04 )

= 12 x 10³ J .

b )

At constant temperature work done

= n RT ln v₂ / v₁

= PV ln v₂ / v₁

= 200 x 10³ x .04 ln .1 / .04

8 x 10³ x .916

= 7.33 x 10³ J .