The document discusses minerals found in the Earth's crust including metals like gold and silver as well as natural compounds such as oxides, carbonates, and sulphides. It describes properties of minerals such as hardness as measured by Mohs scale, solubility in water, and how they are affected by heat. Key mineral compounds mentioned are hematite, cassiterite, calcite, malachite, iron pyrite, and galena; and how minerals like metal sulphides and carbonates decompose when heated.

1. Minerals in the Earth’s Crust

2. Elements in the Earth’s crust

3. Gold Silver Platinum Natural elements

4. Natural compounds- oxides Haematite – iron oxide Cassiterite – tin oxide

5. Natural compounds - carbonate Calcite – calcium carbonate Malachite – copper carbonate

6. Natural compounds - sulphides Iron pyrite – Iron sulphide Galena – Lead sulphide

7. Hardness of minerals Solubility of minerals in water Action of heat on minerals Properties of minerals

8. Can be measured using Mohs’ scale The hardest is diamond (10) The softest is talc (1) Hardness of minerals

9. Most minerals are insoluble in water Only oxides, sulphates and carbonates of potassium and sodium are soluble in water Solubility in water

10. Most metal oxides are stable, do not break down when heated, except less reactive metals. Mercuric oxide mercury + oxygen Effect of heat

11. Very hard except oxides of potassium, sodium, calcium and magnesium Donot dissolve in water Do not decompose on heating except mercury oxide Metal oxides

12. Break down into metal oxide and sulphur dioxide when heated Iron sulphide iron oxide + sulphur dioxide Sulphur dioxide bleaches acidified potassium manganate(VII) solution from purple to colourless Metal sulphide

13. Metal carbonate break down into metal oxide and carbon dioxide when heated Calcium carbonate calcium oxide + carbon dioxide Metal carbonates