- #1

zwambooo

## Homework Statement

2kgs (total mass) of steam goes through a revesible isothermal expansion at 500 degrees celcius. During the expansion the pressure drops from 300 kpa to 200 kpa.

What is the heat absorbed by the steam during this process?

## Homework Equations

U=W and W=nrt ln(v2/v1)

## The Attempt at a Solution

Steam cannot be assumed to be an ideal gas atleast to my knowledge. When I google Reversible Isothermal Expansion all i get is that W is given by, nRT*ln(v2/v1). I cannot imagine the W=nRT*ln(v2/v1) being used in this specific problem. This formula would not give a numerical answer anyway, because the problem states no information about volumes.In a isothermal expansion: there is no change in internal energy so it is 0, and the work is done by the system so W is positive Q=+W.. So how do i calculate this W(heat absorbed by the steam) inthis case? is there any magical formula:)

thank you for all input:)!