CHM1 12Example1 Collection

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SolutionTo find internal energy, ?U, we must consider the relationship between the system and the surroundings. Since the First Law of Thermodynamics states that energy is not created nor destroyed we know that anything lost by the surroundings is gained by the system. The surrounding area loses heat and does work onto the system. Therefore, q and w are positive in the equation ?U=q+w because the system gains heat and gets work done on itself.

?U = (62J) + (474J); ?U = 536J