## Ideal Gases

AtreyiMitra2L
Posts: 169
Joined: Fri Sep 29, 2017 7:03 am
Been upvoted: 1 time

### Ideal Gases

Why is it that with ideal gases, there is no change in internal energy? Thank you!

Sean Monji 2B
Posts: 66
Joined: Fri Sep 29, 2017 7:06 am

### Re: Ideal Gases

Ideal gases are hypothetical in that all collisions between gas molecules are perfectly elastics and no energy is lost to collisions with the container, thus no energy can be lost (if nothing about the system is changing).
Of course, the energy of an ideal gas can change depending on the problem
Most problems concerning use the ideal gas law (PV=nRT) where you have to figure out whether there is a change in internal energy.
If you were to increase the temperature of the system by adding heat, there will be an increase in energy. Energy and temperature are directly related in ideal gases.
But if you increase pressure and decrease volume in a way that there is no temperature change, then there will be no change in energy of the gas (called an isothermal process).
Hope that helps