# Quick questions about ideal gases

1. Feb 21, 2012

### jean28

1. The problem statement, all variables and given/known data
Hey guys, im having trouble understanding how the ideal gases behave and I got these 3 questions in homework:

If an ideal gas is transferred, at constant temperature, 10 Joules of heat, does the internal energy change?

If an ideal gas is transferred, at constant pressure, 10 Joules of heat, does the internal energy change?

If an ideal gas is transferred, at constant volume, 10 Joules of heat, does the internal energy change?

2. Relevant equations
im guessing pV = nRT

3. The attempt at a solution

Im guessing that it changes with constant temperature, but im not too sure about the other two. Could anyone explain to me why the internal energy does/does not change?

2. Feb 21, 2012

### ehild

Do you know the First Law of Thermodynamics? What is heat capacity at constant pressure and at constant volume of an ideal gas? How does the internal energy of an ideal gas depend on temperature? If you can not answer these questions, read your lecture notes. And if you still are not able to do your homework, come back.

ehild