Particle movement Flashcards
Internal energy
All particles have kinetic energy from vibrating or moving
They also have potential energy from intermolecular forces
The internal energy is the total kinetic and potential energy stored in a system of particles
Heating effect on internal energy
Increases kinetic energy causing particles to move more
Can cause changes of state
This does not effect the number of particles/mass
We can reverse these changes as they are physical changes
Evaporation
When a liquid turns to a gas but only on the surface of a liquid
Specific latent heat of fusion
The amount of energy required to change 1kg of solid to a liquid with no change in temperature
Specific latent heat of vaporisation
The energy required to change 1kg of a liquid to a vapour with no change in temperature
How to find the energy for a change in state
Mass x specific latent heat
Specific heat capacity
Amount of energy needed to raise 1kg of a substance by 1°C
Change in thermal energy
change in thermal energy = mass × specific heat capacity × temperature change
Heating and cooling graphs
These graphs show the heating or cooling of a material
When the material changes state, the material doesn’t increase/decrease as that heat energy is being used to break the bonds between particles
Gas pressure
Due to particles colliding with the walls of the container that the gas is in, the gas particles are exerting pressure
Because it causes a force at right angles to the container
How can we increase gas pressure?
increasing the temperature, the kinetic energy increases so particle movement increases
Decrease volume of container
What is pressure measured in?
Pascals Pa
Gas pressure and volume equation
Gas pressure x volume = constant
ONLY IF THE TEMPERATURE IS CONSTANT
Therefore pressure and volume inversely proportional
Work on a gas is done by?
Apply a force to container
Because we applied a force, work is done and so we have transferred energy to gas particles
How does work done effect a gas?
Increase internal energy of particles
Therefore Increase kinetic energy of the gas
And so have increased the temperature
