I had already posted a question which went dead soon about thermodynamics equation of first law.It states: Heat supplied=Internal energy+Work done
But doesn't the Internal energy=Potential Energy+Kinetic Energy+...other many energies? So the equation now is Heat supplied=K.E+P.E+....+Work done But doesn't the work done on or by a system is stored as potential energy itself?Then why do we write both P.E and dW in the equation of the first law? Why isn't Heat supplied=Change in internal energy correct?
If this were done in vacuum would there still be work done against something or what?Please help