Particle model of matter - Paper 1 Flashcards
To revise particle model of matter. (paper 1)
State the equation with all units for density
Density = mass / volume
Density - kg/m3
mass - kg
Volume - m3
How can the density of a regular shaped object be found?
Find mass using an electronic balance.
Find volume using a ruler to measure the length of each side
Then the equation volume = l x l x l
Use the density equation Density = mass / volume
How can the density of a irregular shaped object be found?
Find mass using an electronic balance.
Find volume using a eureka can
Use the density equation Density = mass / volume
How can a eureka cab be used to find the volume of an irregaulr object?
Fill the eureka can with water
Place the object in the water.
The volume of water will rise by the exact volume as the object.
Collect the dispalced volume of water and measure with a measuring cylinder.
How can the density of a liquid be found?
Find the volume using a measuring cylinder
Place an empty measuring cycling on an electronic balance and record the mass.
Add the liquid and record the new mass.
calculate the mass of the liquid (new mass - old mass)
Use the density equation Density = mass / volume
Describe the state changes in melting
Solid to liquid
Describe the state changes in freezing
Liquid to solid
Describe the state changes in evaporating
Liquid to gas
Describe the state changes in condensing
Gas to liquid
Describe the state changes in sublimation
Solid to gas (missing out the liquid stage)
Define internal energy
Energy is stored inside a system by the particles
State the equation for internal energy
Internal energy = Kinetic energy + potential energy
Why does heating always increase internal energy
Heating will either cause the substance to heat up and its kinetic energy to increase or the substance will change state and the internal energy will increase
If a substance is heating up what factors affect the increase in temperature?
- The mass of the substance
- The material ( the specific heat capacity)
- The rate at which energy is supplied
Define specific heat capacity
The specific heat capacity of a substance is the amount of energy required to raise the temperature of one kilogram of the substance by one degree Celsius.
State the units for specific heat capacity
J/kg °C
When a substance changes state why doesn’t the temperate rise?
All the energy is being used to break the bonds and increase the internal energy
Define specific latent heat
The specific latent heat of a substance is the amount of energy required to change the state of one kilogram of the substance with no change in temperature.
State the difference between the latent heat of fusion and vaperisation
latent heat of Fusion is when a solid changes to a liquid
latent heat of Vaporisation is when a liquid changes to a gas
State the units of latent heat
J/kg
Describe the motion of gas particles
constant random motion
As a gas is heated how does the particle motion change?
Particles move faster as they have more kinetic energy
What causes gas pressure
Moving gas particles colliding with a container/object. This pressure will always create a force at a right angle to the container.
Explain the relationship between the temperature of a gas and its pressure?
As temperature increase the pressure increases. this is because the particles have more kinetic energy and move faster. This means there are more collisions each second
State the units of pressure
Pascals (Pa)
If the volume of a container increases what effect will this have on pressure?
As volume increase pressure decreases. It is an inversely proportional relationship. A large volume will mean less collisions per second
When work is done on a gas trying to compress it how does this affect the temperature and internal energy
Work done on the gas makes the particels move faster so they gain kinetic energy. This increases internal energy.
What is the average kinetic energy of the molecules related to?
The temperature of a gas
What happens to kinetic energy if the temperature of a substance is increased?
The total kinetic energy of the particles increases and so the internal energy increased
What is latent heat?
The energy transferred to or from a substance when it changes state
What happens to the temperature of a substance during change of state?
The temperature is constant, so the total kinetic energy of particles does not change
What type of energy changes during a change of state
Potential energy so internal energy must increase as well
While water changes state how could you estimate the power of a Bunsen burner?
Measure the mass of the water that boils.
Calculate the energy transferred to the water using E = mL
Calculate the power using power = energy/time
While water is being heated up how could you estimate the power of a Bunsen burner?
Measure the temperature increase of the water.
Calculate the energy transferred to the water using E = mass x shc x temperature change.
Calculate the power using power = energy/time
