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Physics: Calculate the PV work that is done ON the system

1.) What is the PV work that is done ON the system when
a.) 20J of PV work is done on the surroundings W(system)=
b.) one mole of gas is generated in a chemical reaction at 0 Celsius and 1 atmospheric pressure
c.) A chemical reaction occurs where the volume decreases by 600L

Solution Preview

See attached file for graphics.

Now Let us start the work with the correct explanation.

Please understand that, when a gas expands, it will do a work on the surroundings and when it contracts, work will be done on it ( naturally by the surroundings. ) I think you are getting the logic here.

Now let us say a gas changes its volume ( it may be expansion or compression,) at a constant pressure, then the work done (by the gas OR on the gas ) can be given by

W = PV. (I gave the derivation for this in the attached file.)
Now coming to your set of problems, it has been asked to find out the work done ON the SYSTEM in all the cases.

1) In the case of first problem, it is clearly given that, a 20J of PV Work is done on the ...

Solution Summary

The expert calculates the PV work that is done on the system.