Chapter 21:Hydrogen and water

Hydrogen(H2)

• Simplest molecule made up of two hydrogen atoms joined together by a single covalent bond

Test for hydrogen

• With a rlighted splinter, hydrogen gas makes a pop sound. It burns with a blue flame and produces water.

Water

• Compound made up of two hydrogen and one oxygen.

Uses of water

• Essential for life
• Cooling power stations
• Drinking
• Domestic uses
• Manufacturing of drinks
• for body activity
• Metabollic reactions

Testing for water

• Add to white anhydrous copper(II) sulphate Which turns blue only with water.

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Water pollution

• Fertilizers drained into rivers and streams
• Oil spillage in sea
• Industrial discharge
• Bad sanitation
• algae growth

Water purification

• Filtered through beds of gravel and eventually sand to remove any fine solid particles.
• Water is chlorinated to kill harmful bacteria sometimes
• Flouride salts are added to prevent tooth decay.

Desalination

• Conversion of sea water into drinking water.
• Solar desalination is polular and is easy and cheap.

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