Particle model of matter Flashcards
How do you calculate density?
Density = mass / volume
What is thermal equilibrium?
If two objects are placed together, thermal energy will be transferred between them. If the objects are different temperatures, the net direction of thermal energy flow will be from the hotter object to the colder object. Once the objects are the same temperature, there is no more net flow of thermal energy between them as the objects are in thermal equilibrium
What is convection?
How heat is transferred within liquids and gases (fluids)
What is conduction and how does it happen?
Conduction is how heat is transferred within solids
The heat is passed on through vibrations of the particles. These vibrations get bigger when the solid has more energy, like when it’s being heated
As the particles vibrate, they collide with neighbouring particles, passing on the vibrations
Why are metals better conductors of heat?
Because they contain free electrons that gain more kinetic energy and collide more often with other free electrons and ions so energy is transferred more quickly
What is internal energy?
It is the sum of all the kinetic and potential energies of the individual particles
What is specific heat capacity and how do you calculate it?
The amount of energy required to raise the temperature of 1kg of the material by 1 degree Celsius assuming there’s no change of state
Specific heat capacity = energy supplied / mass x temperature change
What is specific latent heat and how do you calculate it?
The amount of energy needed to change 1kg of substance from one state to another provided the temperature is constant
Energy = mass x specific latent heat
What is pressure and how do you calculate it?
It is defined as the force per unit area
Pressure = force / area
What does Boyle’s law state?
For a fixed mass of a gas at constant room temperature, the volume is inversely proportional to the pressure
Pressure x volume = constant
p1v1=p2v2
What is thermal conductivity?
A measure of how good a conductor the material it is by the energy transfer through the material per second
Why doesn’t the temperature change during the melting or boiling / condensing or freezing of a substance?
Because all of the energy going into the substance goes into breaking the bonds / creating the bonds
