Physics - in book

- Fixed, fixed, higher

- Not fixed, fixed, medium

- not fixed, not fixed, lowest

Sublimating

Melting

Freezing

Evaporating/boiling

Condensing

Sublimating

- As a liquid warms up, the average speed of the molecules in it increases. - Not all the molecules in the liquid will be travelling at the same speed. - The faster molecules with more energy escape from the surface of the liquid, leaving behind the slower molecules with less energy.

- The density of an object is defined as the mass per unit volume. - P can stand for density - Equation: Density = mass/volume

Kg/m3

kg

m3

- The particles in solids, liquids and gases have kinetic energy because they are always moving. - They also have potential energy because their motion keeps them separated. - The particles in gases have the most potential energy because they are the furthest apart. - The internal energy of a system is the total kinetic energy and the potential energy of all the particles in the system.

- Describes the average kinetic energy of the particles in a substance.

- Particles can also have potential energy. When the bonds between particles are broken the particles gain potential energy. When new bonds are made between the particles they lose potential energy

The specific heat capacity is the amount of energy needed to change the temperature by 1 degreesC of 1kg of mass of the material.

amount of energy = mass of material x SHC x temperature change in joules (J) in kilograms (kg) in degrees celsius

- Specific latent heat is the amount of energy needed to COMPLETELY change the state of 1kg of a material without changing the temperature. - Latent heat is measured in joules per kilogram or J/Kg for short.

Amount of energy = mass of material x latent heat (E = mxl) in joules in kilograms in J/Kg

- The amount of energy needed to cause an object to melt.

- The amount of energy needed to cause an object to boil.

- As more bonds need to be broken to turn a liquid into a gas (boiling) which requires more energy.