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The properties of mineral. Different minerals have different characteristics. Mineral possess different characteristicc in term of:
1. Hardness
2. Solubility in water
3. Effect of Heat
HARDNESS
Hardness of mineral refers to the resistance offered by the mineral on being scratched.
The hardness of a mineral is measured In Mohs unit.
Most mineral are hard. This mineral can only be scratched by hard objects such as knives.
Nevertheless, hard mineral can scratch softer minerals.
All mineral made up of….Carbonate….Oxide….Sulphide compound are HARD
(e.g Iron oxide, Calcium carbonate, Zinc sulphide)
Diamond is the HARD mineral, while Talc is the softest mineral
Most minerals exists in the form of compounds like
1. oxides,
2. sulphides
3. Carbonates
Oxides, sulphides and carbonates are usually hard minerals.
SOLUBILITY
All minerals of METAL OXIDES, SULPHIDES, CARBONATES are insoluble /does not dissolve in water
EXCEPT minerals of metallic Potassium and sodium compound.
EFFECT OF HEAT
Metal Carbonate
All metal carbonate DECOMPOSE when HEATED.
EXCEPT Potassium carbonate, Sodium carbonate because both of the metal are very stable.
The heathing of metal carbonate form Metal oxides and carbon dioxide gas.
Silicon Compounds
Silicon is the second most abundant element in the Earth’s crust
Silicon usually exist in the form of
1.Silica (Silicon. Oxygen) or (silicon dioxide)
2.silicates (Silicon. Oxygen.Metal)
Silica
The chemical compound silicon dioxide also known as silica.
Silicon + Oxygen -------- Silicon dioxide (silica)
Example of silica are sand, quartz and flint.
Pure silicon is used to make electronic chips also known as silicon chips
Properties of silicon compounds
1.Silicon compounds are very stable
2.Silicon compounds
do not dissolve in water
do not react with acids
do not decompose when heated
Uses of silicon compounds
Mica
Used in heating appliances as electrical insulators
Quartz
Manufacture of glass
Sand
Manufacture of glass
To make container
To make insulators
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