Chemistry - Topic 1

Chemistry - Topic 1

1. balancing equations

   • work out the elements' valencies
   • This is an unbalanced equation: S + O2 --> SO3
   • equations must always be balanced
   • This is a balanced equation: 2S + 3O2 --> 2SO3

2. Distillation

   • Simple Distillation
   • Fractional Distillation
     • fractional distillation is a more effective way to separate liquids from each other by using their boiling points.

3. chromatography

4. ions and isotopes

   • atoms are neutral because they contain the same number of positive protons as negative electrons
   • ions are particles that contain a different number of protons and neutrons
   • for example: an atom has 11+ protons and 10- electrons. this means it is an ion because it has an unequal amount of protons and electrons

5. atoms

6. history of the atom

7. Elements and mixtures

   • a mixture is a group of elements, compounds and molecules that are not chemically combined
   • an element is a pure substance that consists of the same type of atom
   • elements cannot be broken down any further

8. electronic structure