# Problems Involving Thermodynamics

A piston cylinder assembly whose piston is resting on a stop contains 400 L of helium gas, initially at 200 kPa and 25 degrees celsius. The mass and the atmospheric pressure acting on the piston are such that a pressure of 500 kPa is required to raise it. At the final state, the volume of helium gas is doubled.

a) Calculate the mass of helium in the cylinder.

b) Determine the boundary work done during this process in kJ.

c) Assuming a constant specific heat of helium during this process, determine the heat that must be gained or lost, in kJ.

https://brainmass.com/physics/first-law-of-thermodynamics/problems-involving-thermodynamics-461516

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a) The mass of helium in the cylinder can be calculated from the ideal gas law.

b) In order for the helium to lift ...

#### Solution Summary

In this solution, we solve three problems involving thermodynamic properties of helium gas.