Chemical properties of water - has a polar nature - the molecule of water is a dipole - can form hydrogen bonds (that's why it has relatively high melting and boiling point temperatures) - it is a good solvent due to its polarity (ionic and polar substances such as acids, alcohols, and salts are relatively soluble in water, and non-polar substances such as fats and oils are not) - water is amphoteric: it can be an acid or a base in chemical reactions
When water reacts with an acid, it behaves like a base; when it reacts with the base, it behaves like an acid:
- When a salt of a weak acid or of a weak base is dissolved in water, water can hydrolyze the salt:
Na2CO3 + H2O = NaOH + NaHCO3
- water can be a ligand in transition metal complexes. Typically it's a monodentate ligand, that forms only one bond with the central atom - Water contains hydrogen in oxidation state +1 and oxygen in oxidation state −2. It can oxidize substances with reduction potential below the potential of H+/H2 (hydrides, alkali and alkaline earth metals). But such as aluminum, are oxidized by water as well, but their oxides are not soluble, and the reaction stops because of passivation.
2Na + 2H2O = 2NaOH + H2
- Water also can be oxidized, emitting oxygen gas 4AgF2 + 2H2O = 4AgF + 4HF + O2