Chemistry basics

Solvent - liquid that dissolves substances.

Salt - mad when an acid reacts with an alkali, carbonate or metal.

Mixture - made from molecules of elements and o pounds that are mixed together, without chemical bonds.

Compound - a substance that is made of only one type of atom.

Element - made from atoms of different elements joined by chemical bonds

Metal - oftern giant structures that are good conductors of heat and electricity.

Left hand side - metals
Right hand side - non metals
All metals are solid at room temp. except mercurey, which is a liquid.
All non metals are gases and solids at room temp. except bromine, which is a liquid.

Group 1 - alkaline metals
Group 2 - alkaline earth metals
Group 7 - halogens
Group 9 - noble gases

The diatomic elements are:

H2
N2
O2
F2
Cl2
Br2
I2

Chromatography - sipolvebt travels up the paper, and different soluble substances in a mixture get carried along different speeds so they separate out.

Dissolving - the Saltgate breaks up into tiny particles that mix with the particles of the solvent to make a solution the solvent is still all there so the mass of the solution the same is the mass of the solute and solvent added together.

Evaporating – the liquid evaporates and leave the solids behind.

Filtering - undissolved particles are too big to get into tiny gaps in the filterpaper, so they get trapped. The liquid and any dissolved solids go through the filterpaper.

Simple distillation - used for separating out a mixture of liquid and solid. Liquid is heated and evaporate off to form a gas, the gas Is them condensed and the liquids and solids have been separated.

Fractional distillation - Use when separating two liquids. The liquids are boiled and because they have different boiling point will evaporate different temperatures, so they can be separated.

Isotopes are atoms of the same element which contain different numbers in their nuclei.

What’s the same:

– number of protons
– all chemical reactions
– atomic number

What’s different:

– Number of neutrons
– mass number
– physical properties