### Solution Found!

# Solved: A gas expands and does P-V work on the

**Chapter 6, Problem 17P**

(choose chapter or problem)

**QUESTION:**

A gas expands and does \(P-V\) work on the surroundings equal to \(325 \mathrm{~J}\). At the same time, it absorbs \(127 \mathrm{~J}\) of heat from the surroundings. Calculate the change in energy of the gas.

### Questions & Answers

**QUESTION:**

A gas expands and does \(P-V\) work on the surroundings equal to \(325 \mathrm{~J}\). At the same time, it absorbs \(127 \mathrm{~J}\) of heat from the surroundings. Calculate the change in energy of the gas.

**ANSWER:**

Step 1 of 2

The goal of the problem is to calculate the change in energy of the gas.

Given:

w = - 325 J

q = 127 J

The change in energy of the gas is calculated using the formula:

U = q + w

q = heat

w = work done

The expansion of gas indicates that there is an increase in the volume of the gas. Therefore, ‘w’ gets - sign and the system absorbs heat. Hence, ‘q’ gets + sign.

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