Question

In an expansion of gas, 500 J of work are done by the gas. If the internal energy of the gas increased by 80 J in the expansion, how much heat does the gas absorb?

(a) 580 J
(b) 420 J
(c) 620 J
(d) 580 J

Answer 1

Using the first law of thermodynamics, ΔU = Q - W, and rearranging for Q (heat absorbed), we find that the gas absorbs 580 J of heat during the expansion when 500 J of work is done by the gas and the internal energy increases by 80 J.

Step-by-step explanation:

In an expansion of gas where 500 J of work are done by the gas and the internal energy of the gas increased by 80 J, we can determine the amount of heat absorbed by the gas using the first law of thermodynamics:

First Law of Thermodynamics: ΔU = Q - W

Where ΔU is the change in internal energy, Q is the heat absorbed by the system, and W is the work done by the system. Rearranging the formula to solve for Q gives us:

Q = ΔU + W

Substituting the given values we get:

Q = 80 J + 500 J = 580 J

Therefore, the gas absorbs 580 J of heat during the expansion.