Exam 3 - Kinetic Molecular Theory Flashcards
The kinetic molecular theory…
…Describes why gases behave like they do
Forces between gas molecules are negligible
True
Collisions between gas molecules are elastic
True
Pressure is proportional to…
…the number of collisions and the speed of collisions
Temperature and the average velocity of the molecules in a gas are…
…directly proportional to each other
Speed and average kinetic energy are…
…directly proportional to each other
What happens if there is an increase in volume at a constant temperature?
When volume increases, the number of collisions per unit time decreases, leading to a decrease in pressure
What happens if there is an increase in temperature at a constant volume?
When temperature increases, the velocity of the gas molecules increases, so there will be more collisions with the container per wall per unit time, leading to an increase in pressure.
What is effusion?
It is the escape of a gas through a hole into an evacuated space
What is diffusion?
It is the spread of a substance through a space or another substance.
What happens if two gas containers are opened?
The lighter molecules will diffuse faster
What two conditions affect diffusion?
Speed of the gas molecules and collisions with other molecules
Gas molecules are very slow; that is why it takes a long time for them to travel a significant distance.
False. They are quite fast (average velocity at 500m/s), but the collisions between the molecules will increase their travelling time.
What is the distance travelled by a molecule before colliding with another molecule called?
Mean Free Path; it is the distance between collisions
A gas molecule trajectory is not affected by the collision with other molecules.
False. Upon a collision, they change directions
