6.3.1 Changes of state and the particle model Flashcards
density is measured in?
kg/m3
The particle model can be used to explain?
the different states of matter
* differences in density.
when substances change
state (melt, freeze, boil, evaporate, condense or sublimate) what happens to the mass?
mass is conserved
Changes of state are
physical changes
how do physical changes differ from chemical changes?
because in physical changes the material recovers its original properties if the
change is reversed.
what is energy stored in a system by?
Energy is stored inside a system by the particles (atoms and
molecules) that make up the system
Energy is stored inside a system by the particles (atoms and
molecules) that make up the system. what is this called?
internal energy
what is internal energy?
Internal energy is the total kinetic energy and potential energy of all
the particles (atoms and molecules) that make up a system.
Heating changes the energy stored within the system. How?
by increasing the energy of the particles that make up the system.This either
raises the temperature of the system or produces a change of state.
If the temperature of the system increases:
The increase in temperature depends on the mass of the substance
heated, the type of material and the energy input to the system
what is latent heat?
The energy needed for a substance to change state
When a change of state occurs, what happens?
the energy supplied changes
the energy stored (internal energy) but not the temperature
what is the specific latent heat of a substance?
the amount of energy
required to change the state of one kilogram of the substance with
no change in temperature.
Specific latent heat of fusion
change of state from solid to liquid
Specific latent heat of vaporisation
change of state from liquid to
vapour
