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2 years ago

1. A gas expands and does p-v work on the surroundings equal to

Chemistry

1 answer:

azamat2 years ago

3 0

The change in energy of the system : -63 J

<h3>Further explanation</h3>

Given

279 J work

216 J heat

Required

The change in energy

Solution

Laws of thermodynamics 1

ΔU=Q+W

Rules :

receives heat, Q +
releases heat, Q -
work is done by a system, W -
work is done on a system, W +

a gas work on the surrounding : W =-279 J

a gas absorb heat from surrounding : Q = +216 J

Internal energy :

= -279+216

= -63 J

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