Gas Particles
What are gas particles doing all the time?
They move continuously in random directions.
When gas temperature increases, what happens to average particle speed?
The particles move faster on average.
What happens to the space available to gas particles when container volume decreases?
The particles have less space.
What is atmospheric pressure?
The pressure exerted by the air surrounding Earth.
What is heated inside the aluminum can in the demonstration?
A small amount of water.
What happens when a gas particle hits a container wall?
It collides with the wall and exerts a force on it.
At constant volume, what generally happens to pressure when a gas is cooled?
Pressure generally decreases.
If the same gas is squeezed into a smaller volume at constant temperature, what happens to pressure?
Pressure increases.
Which pressure is greater in the crushed-can situation: inside or outside?
The atmospheric pressure outside the can is greater.
What forms when the water is heated?
Water vapor (steam).
What is the combined effect of countless particle collisions with surfaces?
They produce gas pressure.
Why do warmer gas particles usually produce greater pressure at the same volume?
They move faster and collide with the walls more forcefully on average.
Why do particles hit the walls more often when the volume is reduced?
The walls are closer together, so particles reach them more frequently.
If pressure inside a container is lower than pressure outside, which way is the net force?
Inward, toward the lower-pressure region.
What happens to water vapor when the can cools rapidly?
It condenses into liquid water.
Why do gas particles create pressure on every side of a container?
They move randomly in all directions and collide with all the walls.
In the simulation, what should stay constant when testing temperature's effect on pressure?
Keep the container volume and amount/number of gas particles constant.
In a volume investigation, which two variables should be kept as constant as possible?
The amount/number of gas particles and the temperature.
Complete the comparison: inside the can = lower pressure; outside the can = ____ pressure.
Higher atmospheric pressure.
Why does condensation greatly reduce the pressure inside the can?
Much of the water vapor changes into liquid, leaving far fewer gas particles in the vapor state inside.
Explain how particle motion is connected to gas pressure.
Moving particles collide with container walls. These collisions exert force; the combined force per unit area is gas pressure.
A sealed, rigid container of gas is cooled. Explain the pressure change using particle theory.
Particles move more slowly, so their collisions with the walls are less forceful on average; pressure decreases.
Explain why reducing the volume of a gas usually increases its pressure.
The same particles occupy less space and collide with the walls more frequently, increasing pressure.
Why can outside air pressure crush a container when the pressure inside becomes much lower?
The greater outside pressure creates a net inward force on the container.
Explain the complete soda-can crush using at least three linked steps.
1.Heating produces : pressure inside rises
2.Rapid cooling: pressure inside drops
3.Net inward force and crushes the can.