Gas Laws Flashcards
What is the Ideal gas equation
pV = nRT
What is an ideal gas? (4)
A gas that:
. The gas molecules dont interact with each other (no intermolecular forces)
. The molecules are thought to be perfectly spheres
. Follow the gas laws and newtons laws of motion with complete precision
.occupy negligible space compared to the container they’re in
What is Boyle’s law?
Pressure is inversely proportional to volume, providing temperature is constant
Explain Boyles law as volume reduces. (5)
Temperature is constant
As volume reduces
Particles travel a smaller distance when colliding between surfaces within the container
Therefore change in momentum at the surface is greater due to a greater rate of particles hitting the surface
Meaning a larger force exerted meaning an increase in pressure .
What is Charles Law?
The volume of a gas & its temperature are directly proportional, assuming the pressure is constant
Explain charles law as temperature increases (7)
Pressure is constant
as temperature increases ‘
the velocity of the particles increases due to higher kinetic energies
Less time between collisions with the surfaces of the container
increasing the systems internal pressure from a greater change in momentum at the surface
Internal pressure: External pressure ratio is higher then the original equilibrium met with
This produces a net force outwards that causes the volume to increase until the internal pressure is in equilibrium with the external pressure as it were before
What is Gay Lussacs/ Amonton’s law?
The pressure of a gas & its temperature are directly proportional, assuming the volume is constant
Explain Gay Lussac’s/ Amonton’s law as temperature increases (7)
Volume is constant
as temperature increases ‘
the velocity of the particles increases due to higher kinetic energies
Less time between collisions with the surfaces of the container
Change in momentum at surface is greater due to a higher frequency of collisions
So greater forces exerted on the container
Therefore a greater pressure
What is absolute zero
-273 degrees
Where atoms have no kinetic energy
What is avogadros constant.
the number of atoms there are in 1 mol of a substance
What are the assumptions to ideal gas equations (5)
All collisions between particles and between the wall and particles are elastic collisions
The time for each collision is negligible in comparison to the time taken between collisions
Particles move random and follow newtons laws of motion and the gas laws with complete precision
No intermolecular forced act between particles
Volume of particles is negligible compared to the volume of the container they’re in
What is meant by the root mean square speed
The square root of the (mean of speeds squared of the molecules)
What is brownian motion
Idea that very small objects have random motion in a liquid or gas due to random collisions between molecules in the system.
If this movement occurs more on 1 side of the system then the others, a net force occurs pushing it for an instant.
This is brownian motion which is evidence for the existence of atoms
For a gas to be an ideal gas: (4)
- Intermolecular forces are negligible between molecules
- Gas molecules collide elastically with the wall of the container and between each other
- Moelucles are assumed to be point particles
- Gas completely obeys all gas laws with complete precision
Fill in the table
What is Avogadro’s Law?
Equal volumes of ideal gasses at the same pressure and temperature contain equal amount of particles
