Salts

• SALT: a compound formed from an acid by the replacement of the hydrogen in the acid by a metal.
• Salts are ionic compounds. 
• Preparing Soluble Salts:

  A. Acid + metal / metal hydroxide / metal oxide / metal carbonate
• Preparing Soluble Salts:

  B. Acid + alkali by titration

  Involves the neutralisation of an acid with an alkali. Since both the reactants and products are colourless, liquid indicator is added.

  The acid in the burette is added drop by drop to the alkali until it is neutralised.
• Choosing a method of salt preparation:

  1. Is the metal reactive enough to displace the hydrogen in the acid? (yes - method A, no - method B)
  2. Is the base or carbonate soluble or insoluble? (soluble - method B, insoluble - method A)
• Making salts by precipitation:

  Used to make salts which are insoluble in water. 
• Precipitation: the sudden formation of solid either:

  1. When two solutions are mixed;
  2. When a gas is bubbled into a solution.