Air at 120 kPa and 25ºC in a 2-m3 rigid insulated volume is heated using an electrical resistance heater so that the pressure increases to 800 kPa. Assuming constant specific heats, the entropy change of the air is nearest:

Question

A) 4.82 kJ/K
B) 4.61 kJ/K
C) 4.12 kJ/K
D) 3.82 kJ/K

Answer 1

D) 3.82 kJ/K

The final temperature and the mass are:



The entropy change is then