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# Definition of an ideal gas, ideal gas law

Dive into the dynamics of gas pressure, temperature, and volume. Learn how these factors interplay in the Ideal Gas Equation, PV=nRT. Understand the conditions that define an ideal gas and how this equation can determine pressure, volume, or temperature. Created by Ryan Scott Patton.

## Want to join the conversation?

• How do we conclude that pressure is inversely proportional to volume not volume^(2/3) or something and the same for both of the other factors
• It was through experimentation that scientists discovered the inverse, linear relationship between pressure and volume. The linear nature of the relationship indicated that the exponents for both pressure and volume were 1. The experiment and its resulting data are explained in the Boyle's Law video, which is also in this playlist. :)
• Why would more particles being added when they have volume cause the volume of the container to go down? It's around 4.35
• Just my understanding,
If particles are being added to a container(of vol. Vc) have volume, this would decrease the volume of the container = Vc - total vol. of particles (Not the volume the gas occupies!)
imagine a container, add a rock, what is the volume of the container now? lesser? greater? the same?
what does this mean?
as particles are added, the volume of the container decreases => volume gas can occupy decreases => pressure must increase (p=k/v)
we'd have to take that into account as well which would make our equation more complex.
I hope this helps, if wrong, lemme know
Onward!
(1 vote)
• Is it possible for me to bookmark this or save it for later on my account?
• When does a gas not act like an ideal gas?
(1 vote)
• R always equals.0821 right?
(1 vote)
• not always
Depends on units of pressure and volume.
R=8.314 J per Kelvin mol
R 0.0821 L * atm per mol * K
• What does it mean exactly when you say in minute there are no inter molecular forces? What are those?
(1 vote)
• What do you mean by "collisions are perfectly elastic"()?
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• At , does Scott say "point masses" meaning the mass of the gas is negligible? It just sounds like he said "pointless", but I'm inclined to believe my hearing is failing me.
(1 vote)
• Wouldn't pressure only be directly proportional to the number of moles if volume was assumed to be constant? If you increased the number of moles the volume would increase in a directly proportional manner. While Ideal Gas molecules are of negligible volume, 1 mole of a gas takes up 22.4 L of volume.
(1 vote)
• Is there a vacuum behind your microphone?
(1 vote)