There are 3 methods to prepare salts:
1. Precipitation method
– to produce INSOLUBLE salts
– Reagents: (aqueous) + (aqueous)
– Examples: BaSO4, CaSO4, AgCl, PbCl2 etc.
2. Excess/ICA method
– to produce SOLUBLE salts
– Reagents: (aqueous; usually an acid) + (solid; excess METAL/ METAL OXIDES/ METAL HYDROXIDES/ METAL CARBONATES)
– Note: some metals such as Cu/Ag cannot be used as they are unreactive & Group I metals such as Na/K as they are too reactive**
– Examples: CuSO4, CuCl2, Ba(NO3)2 etc.
3. TITRATION method
– to produce SOLUBLE A1 (Ammonium + Group I) SALTS
– Reagents: (aq; acid) + (aq; base)
– Examples: NaCl, KCl, NH4NO3 etc.
– you have to be very familiar with the solubility table; to produce insoluble salts there is only one method – PRECIPITATION.
– However, if the salt you want to produce is soluble, you have to determine if it is an ‘A1’ salt. If it is, use the TITRATION method. If it is not ‘A1’ salt, use the EXCESS method.
– Remember A1 (Ammonium + Grp I) to get your A1 in Chem!
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