Hydroxide Ion (Chemistry)
Revision as of 19:59, 6 January 2019 by NRJC (talk | contribs) (NRJC moved page Hydroxide Ions (Chemistry) to Hydroxide Ion (Chemistry))
Key Stage 4
Meaning
A Hydroxide ion (OH-), is a positive ion of Hydrogen found in acid solutions.
About Hydroxide Ions
- When a basic compound dissolves in water it forms Hydroxide ions.
- Hydroxide ions are responsible for the corrosive properties of alkalis.
Examples
Metal Hydroxides form Hydroxide ions in water.
- NaOH(aq) → Na+(aq)+OH-(aq)
- KOH(aq) → K+(aq)+OH-(aq)
- Mg(OH)2(aq) → Mg+2(aq)+2OH-(aq)
- Ca(OH)2(aq) → Ca+2(aq)+2OH-(aq)
- Al(OH)3(aq) → Al+3(aq)+3OH-(aq)
Metal Oxides react with water to form Metal Hydroxides.
- Na2O(s) + H2O → 2Na+(aq)+2OH-(aq)
- K2O(s) + H2O → 2K+(aq)+2OH-(aq)
- MgO(s) + 2H2O → Mg+2(aq)+2OH-(aq)
- CaO(s) + 2H2O → Ca+2(aq)+2OH-(aq)
- Al2O3(s) + 3H2O → 2Al+3(aq)+6OH-(aq)