The Amphoteric Behavior of Aluminum

Doth either the Sunne take upon him to doe that which belongs to the raine or his son /Esculapius that, which unto the Earth doth properly belong How is it with every one of the starres in particular Though they all differ one from another, and have their severall charges and functions by themselves, doe they not all nevertheless concurre and cooperate to one end  

1-L beaker, magnetic stirrer, hard white card, safety glasses, protective gloves. Chemicals 

6mol/L NaOH, KA1(S04)2 12 H2O, concentrated sulfuric acid, distilled water, universal indicator solution. 

The sulfuric acid solution of the alum is neutralised by NaOH until solid A1(0H)3 is formed according to eqn. 1  

An excess of OH ions leads to the formation of the tetrahydroxoaluminate complex, which is very soluble in water, and related species according to eqn. 2  

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