Oxygen with a mass of 64 g was heated at 20 K at constant pressure. Find work done with gas.

Let’s start with a short entry given:

m (O2) = 64 grams;

T = 20 K (at constant pressure);

To find:

A -?

Let us apply the first law of thermodynamics to the solution.

So, with the isobaric process, we have:

Q = ΔU + A.

To calculate the internal energy, we apply the formula:

ΔU = 1.5 * v * R * ΔT.

As a result, we got equality:

pV = vRT.

We will find the work done by gas by the formula:

A = v * R * ΔT;

We substitute the values into the formula and perform the calculations:

A = 64/16 * 8.31 * 20 = 664.8 J is approximately equal to 665 J.