P6: Molecules and Matter Flashcards
What is the equation to work out density
Mass/Volume
What is the correct standard unit of density
kg/m3
Kilograms per metres cubed
How do we work out internal energy
Combine the kinetic energy with the potential energy
What happens as we increase internal energy
Both kinetic energy and potential energy increase. This causes a temperature rise
What happens if we heat something
More energy is transferred
What is it called when particles in a substance are constant
Brownian Motion
How do we work out specific heat capacity
Energy / (Temperature X Mass)
What is specific heat capacity measured in
J/Kg 0 c
Joules per kilogram degree Celsius
What is specific latent heat of fusion
Amount of energy needed to turn a solid into a liquid
What happens if increase the temperature of a gas
If we have a container full of gas, as temperature increases, pressure increases
What is density
The mass per unit volume of a substance
How do we work out the volume of a regularly shaped object
Width X Height X Depth
What is everything made of
Particles
What is internal energy
The total energy stored by particles of a substance
What is the specific latent heat of vaporisation
Amount of energy needed to turn a liquid into a gas
What are the units of specific latent heat
J/Kg
Joules per kilogram
What can the movement of particles be known as
Random
What is specific latent heat
The energy transferred to or from a substance as it changes state
What does the Law of Displacement mean
An object submerged in a fluid replaces the amount of fluid equal to the volume
Order solid liquid gas from least dense to dense, starting with least dense
Gas, liquid, solid
What is the temperature of our body
A measure of energy in kinetic stores of particles
What happens if we increase body temperature
Kinetic energy stores of body’s particles are increased and internal energy stores of body’s particles are also increased
What is specific heat capacity
The amount of energy required to raise the temperature of 1kg of that substance by 1 degrees Celsius
How can we increase the internal energy of our body
A heater, via a joulemeter.
How do we measure our body temperature
Measure the start and maximum body temperature at the end
What happens when we heat a liquid
When heating a liquid, particles move energetically until they have enough energy to completely escape from forces between them. Particles become a gas and move freely. The temperature needed for this to happen is the boiling point. We call this vaporisation
What happens when we melt a solid
When a solid turns into a liquid, solid particles vibrate energetically until having enough energy to overcome forces between them. This is when it melts. The temperature needed for this to happen is the melting point. We call this fusion
What do we call it when a liquid changes to a gas, and vice versa
Latent heat of vaporisation
What do we call it when a solid changes to a liquid and vice versa
Latent heat of fusion
Do we measure specific latent heat
No
How can we determine water as our specific latent heat of fusion
Use the equation
Energy/Mass
- Gently heat the ice funnel until it melts.Then measure the mass of that
- Measure the amount of energy supplied by the heater via a joulemeter
- Finally calculate the specific latent heat of fusion
How can we determine water as our specific latent heat of vaporisation
Use the equation
Energy/Mass
- Measure the mass of water in a beaker
- Boil the water, then measure the mass of water again
- Use the equation
Change of mass = Start mass - End mass - Using a joulemeter, measure the energy amount supplied by a heater
- Finally calculate the specific latent heat of vaporisation
What are gases like in containers
They exert pressure on container walls. Lots of gas particles collide with the container per second.
When colliding with the container walls, the momentum changes and it bounces back off the wall
This exerts a force on the particle and wall
Pressure exerted on a wall is equal to the force (of ball) per unit area (wall hit)
How do we calculate constant
Pressure X Volume
What is the change of momentum
Impulse
How do we calculate the momentum
Mass X Velocity
What happens when force in a particle is increased
The surface area remains the same, but the pressure increases
What does the pressure of a gas produce
A net force (sum of all forces) at right angles to container walls
What happens if the temperature of a gas is increased with a fixed volume
Particles collide with the container walls with more force. Therefore the pressure is increased. The container then expands (increase volume) if able to as the gas pushes it outwards
