Compounds and Mixtures

1
Compounds and Mixtures
2
Elements
If a solid, liquid or gas is made up of only one
type of atom we say it is an element. For
example, consider a tripod made up of iron
3
Compounds
Compounds are different to elements. They
contain different atoms. Here are some examples
4
Some Simple Compounds
Carbon dioxide, CO2
Water, H2O
Ethyne, C2H2
5
Making Compounds

• Compounds are made when two or more elements (or
  compounds) go through a chemical reaction.
• For example
• When carbon reacts with oxygen it usually forms
  ____ _________
• When oxygen reacts with hydrogen it could form
  ______
• When iron reacts with oxygen it could form ______
  ______
• There are usually tell-tale signs to show when
  a compound is being made, such as bubbling, heat
  given off, colour changes, fizzing etc.

Water, iron oxide or carbon dioxide?
6
Naming compounds
7
Naming Compounds
8
Naming compounds
Rule 3 If two identical elements combine then
the name doesnt change
9
Mixtures
Before
After
100 g
105 g
10
Element, mixture or compound?
11
Air
Air is a mixture
21
18
79
79
12
Separating air
Air can be separated into the different gases
that make it up. To do this you first have to
cool air down to -2000C and turn it into a liquid