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3 years ago

A system gains 687 kJ of heat, resulting in a change in internal energy of the system equal to 156 kJ. How much work is done?

Chemistry

1 answer:

Maslowich3 years ago

4 0

Answer:

w = -531 kJ

1. Work was done by the system.

Explanation:

Step 1: Given data

Heat gained by the system (q): 687 kJ (By convention, when the system absorbs heat, q > 0).

Change in the internal energy of the system (ΔU°): 156 kJ

Step 2: Calculate the work done (w)

We will use the following expression.

ΔU° = q + w

w = ΔU° - q

w = 156 kJ - 687 kJ

w = -531 kJ

By convention, when w < 0, work is done by the system on the surroundings.

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2 years ago

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