What is Water (H₂O)?
Water is a simple chemical compound made of two hydrogen atoms and one oxygen atom (H₂O).
It is essential for life and found naturally in three states:
Solid (ice)
Liquid (water)
Gas (water vapor or steam)
Water has no taste, color, or smell in its pure form. It boils at 100°C and freezes at 0°C (at sea level).
It is known as the **universal solvent** because it can dissolve many substances.
What is in Natural Water?
Natural water (from rivers, lakes, taps, wells) contains several substances. These include:
1. Dissolved Gases
Oxygen (O₂):Needed by fish and aquatic animals.
Carbon dioxide (CO₂): Used by aquatic plants for photosynthesis.
Nitrogen (N₂): Comes from the atmosphere.
2. Minerals and Salts
These dissolve in water from soil and rocks:
Calcium
Magnesium
Sodium
Potassium
Chloride
Sulfate
These minerals are important for health but can also make water "hard."
3. Microorganisms
Bacteria
Viruses
Some are harmless, but others can cause diseases like cholera or typhoid.
4. Organic Matter
Decayed plants and animals
Animal waste
These can increase pollution and reduce water quality.
5. Pollutants
Pesticides and fertilizers (from farms)
Industrial chemicals and heavy metals
Oil or sewage
These make water unsafe for drinking and can harm aquatic life.
6. Suspended Solids
Mud
Sand
Clay
These are tiny particles that make water look cloudy or dirty.
Summary
Water may look clean, but it often contains many dissolved or suspended materials. Some are natural and helpful, while others can be harmful. That’s why water treatment and purification are important before using it for drinking or cooking. Let me know if you want a deeper explanation on any part.
