Chemistry

Compounds

Atoms in different elements that can join together in chemical reactions

Names of compounds

Iron

Lead

Carbon

Calcium

Hydrogen

Potassium

Helium

Copper

Aliminium

Chlorine

Gold

Oxygen

Formulae

Compounds work together to creat water, a compound.

Properties of compounds are usually very different from properties of eletems.

All compounds have a definite compostition

A water molecule always has two hydrogen atoms and one oxygen atom

Waters formulae is always H20

Chemical reactions usually involve a change in appareance, for example, the colour could change and that would be a chemical reaction

A Physical reaction is when something dissolves or a state changes, a state change is when something is a liquid and it turns into a solid, etc etc

All substances can be solids, liquids or gasses.

Some chemicals can be dissolved in water, like salt, sodium chloride

Sugar lumps dissolved in water make a sugar solution

Formulae for salt is NaCl

Adding more sugar will make it more concentrated

A second way to dissolving the substance