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What cause gas pressure?

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Winga:
Is it the repulsion force between gas molecules?

gregpawin:
Presure is merely force over a defined area.  Gas pressure is just the collective force of gas molecules running into a container wall.  Since gas molecules have such small masses, these gas molecules are moving at very fast speeds.

The reason why these things do bounce off the walls and one another is because molecules and atoms have clouds of electrons around them that repel each other, positive repels positive and negative repels negative.  So these things didn't have these repulsive electrostatic forces, they'd just run right through each other.  So you're right.

Winga:
One more thing, pressure increases as temperature increases (keep volume as constant).
So, how temperature affects the electron clouds of the molecules?

jdurg:
As temperature increase, the motion of the atoms increases as well.  (Hence when you are boiling water, the heat causes the water molecules to move around faster and faster until they have so much energy from the heat that they become a gas).  The higher energy/movement of the molecules is also what causes density to decrease as temperature increases.  In the case of the gas, the gas molecules are moving around at a faster rate and with more energy, so the force they exert on each other and the walls of the container increases as well.  

Winga:

--- Quote from: jdurg on August 04, 2004, 04:29:48 PM ---As temperature increase, the motion of the atoms increases as well.  (Hence when you are boiling water, the heat causes the water molecules to move around faster and faster until they have so much energy from the heat that they become a gas).  The higher energy/movement of the molecules is also what causes density to decrease as temperature increases.  In the case of the gas, the gas molecules are moving around at a faster rate and with more energy, so the force they exert on each other and the walls of the container increases as well.  

--- End quote ---
Yes, I know, and I also want to know the increasing movement of the molecules is due to the larger repulsion between them which is caused by the increasing temperature or not.

Thus, higher the temperature, larger the repulsion, faster the movement of molecules.
Is it?

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