Introduction on Particle Theory
A matter is made up from particles that are to small to see.
An atom is the smallest particle. It can not be broken down anymore. It is the smallest recognisable part of an atom.
A molecule is a particle made up of 2 or more atoms chemically bonded together.
An ion is an atom or group of atoms chemically bonded that have an electrical charge.
States of Matter
shape fixed dfaffafdafdasfdasfadfdfaffafdafdasfdshape spreads out to fill container
volume fixed dfaffafdafdasfdasfadfdfaffafdafdasf volume not fixed (expands)
compressability not compressible dfaffafdafdasfd compressability compressible
shape flows easily takes shape of container
compressability not compressible
Diffusion is the spreading out of a substance It occurs in liquids and gases
It occurs because moving particles collide with each other and bouce around
Diffuison can not occur in soilds because the atoms are fixed in place.
The rate of diffuison increases with temperature because the particles are moving faster.
Small light particles diffuse faster than large heavy particles
Diffusion is faster in gases than liquids.
Elements, Compounds and Mixtures
There are 92 stable elements
They are arranged by their atomic number from smallest to largest.
An element is a pure substance made up of one type of atom
A compound contains atoms of 2 or more different elements
They are chemically bonded together
Compounds can only be separated chemically not physically.
A mixture contains 2 or more substances which are mixed together but not chemically bonded
They can be physically seperated
Separation of Mixtures
Filtration - The residue (solid) is trapped in the filter paper, when the liquid or solution passes through.
Centriuge - Inside the centrifuge, test tubes get spun around so the solid gets flung to the bottom and collects there.
Evaporation - The solution is heated to evaporate the solvent leaving the solute behind.
Simple Distillation - The solution is heated until it boils. The vapour rises and enters the condenser. It cools, condenses and is then sperate from the solute.