Question

One mole of ideal gas goes through an isothermal compression at a temperature of 12 °c. if 7.80 × 102 j of work is done in compressing the gas, what is the change in entropy of the system?

Answer 1

We calculate the entropy of an ideal gas follows:

For an isothermal compression, change in internal energy is equal to zero.
Thus, the heat added to the gas is equal to the work done on the gas which is given as 7.80 × 10^2 J.

Entropy would be 7.80x10^2/(12+273.15) = 2.74 J/K