Acids and Bases
The pH scale is a measure of the acidity or alkalinity of a solution.
Hydrogen ions, H+(aq), make solutions acidic.
Hydroxide ions, OH-(aq), make solutions alkaline.
In neutralisation reactions, hydrogen ions react with hydroxide ions to produce water. This is represented by the equation:
H+(aq) + OH-(aq) → H20(l)
Metal oxides and hydroxides are bases.
Soluble hydroxides are called alkalis.
Which salt will be produced in any reaction between an acid and a base/alkali depends on:
Which acid is used -- hydrochloric acid produces chlorides; nitric acid produces nitrates; sulphuric acid produces sulphates
Which metal is in the base/alkali
Ammonia dissolves in water to produce an alkaline solution and it is used to produce ammonium salts, which are important because they are used as fertilisers.