Chemistry: Preparation of Salts

Acids Reacting With Carbonates

Acid + Carbonate --> Salt + Carbon Dioxide + Water

2HNO3 + Na2CO3 ---> 2NaNO3 + CO2 + H2O

H2SO4 + CaCO3 ---> CaSO4 + CO2 + H2O

2HCl + CaCO3 ---> CaCl2 + CO2 + H2O

Acids Reacting With Metals

EXAMPLES:

Acid + Metal --> Metal Salt + Hydrogen

H2SO4 + Mg ---> MgSO4 + H2

2HCl + Ca → CaCl2 + H2

Titration

Used when acid is soluble and if the substance being added to the acid is soluble.

Mix two aqueous solutions of
known volume together (for complete
reaction) to form the soluble salt.
Usually between an acid and a base

HCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l)

Titrate acid & base (with indicator)
Determine exact quantities that will completely
neutralise the acid & alkali.
Titrate acid & base again (without indicator)
Salt formed can then be crystallised out in pure
form.

Acids Reacting With Metal Oxides

Acid + Metal Oxide --> Salt + Water

3HCl + Fe2O3 ---> FeCl3 + 3H2O

H2SO4 + CuO ---> CuSO4 + H2O

Acids Reacting With Bases

Acid + Bases --> Salt and Water

HCl + NaOH ---> NaCl + H2O

H2SO4 + 2KOH ---> K2SO4 + 2H2O

CH3COOH + NaOH ---> NaOOCCH3 + H2O

2HNO3 + Ca(OH)2 ---> Ca(NO3)2 + 2H2O

Precipitation

Use when salt is insoluble.

Mix two aqueous solutions together to form the insoluble salt.

2HCl + CaCO3 ---> CaCl2 + CO2 + H2O