SODIUM CHLORIDE

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SODIUM CHLORIDE

• The common salt

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• Common salt is a compound of an alkali metal and
  a halogen.
• all sodium chloride is crystalline. Very large
  cubic crystals, of two, three or more inches in
  size, can be seen in some salt mines

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• It is found in HUGE quantities in the sea and in
  underground deposits.
• Salt even arrives on earth from outer space in
  meteors and its presence on the planet Mars makes
  scientists think life may exist there (in fact,
  scientists speculate that salt-loving bacteria
  live in underground water on Mars -- as they have
  survived in suspended animation for 250 million
  years in Texas)
• Salt solution is often called brine.

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Making sodium chloride
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• The electrolysis of brine is an important
  industrial process.
• Chlorine gas is formed at the positive electrode
  and hydrogen gas is formed at the negative
  electrode.
• A solution of sodium hydroxide is also formed.
• Each of these products is also used to make
  useful materials.

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• Chlorine
• To kill bacteria in drinking water and swimming
  pools.
• In the manufacture of hydrochloric acid.
• To make bleach and disinfectants.
• To make the plastic PVC

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• Hydrogen
• To make ammonia
• To make margarine

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• Sodium hydroxide
• To make soap.
• To make paper.
• To make ceramics.

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The test for chlorine!!!

• It bleaches damp litmus paper!!
• (i.e. turns it white!)

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Electrolysis of NaCl