What is meant by the term amphoteric? and give an example of a reaction using NaOH that could be used to distinguish between a solution of amphoteric AlCl3 and non-amphoteric MgCl2.

The phrase amphoteric describes a compound that reacts with both acids and bases. 

NaOH can react with both AlCl3 and MgCl2 to give a white precipitate but the addition of excess NaOH causes the amphoteric Al(OH)3 to dissove, whereas the magnesium precipitate does not dissolve with excess NaOH.

Al3+(aq) + 3OH-(aq) -> Al(OH)3(s)

Al(OH)3(s) + OH-(aq) -> [Al(OH)4]- (aq)

LL

Related Chemistry A Level answers

All answers ▸

What is meant by terms 'saturated' and 'unsaturated' when applied to alkanes and alkenes? Describe a chemical test to distinguish between the liquids hexane and hexene.


Explain the relative resistance to bromination of benzene compared with alkenes.


Describe and explain the trend in atomic radii across the periodic table


How does increasing/decreasing temperature affect the equilibrium position of the following reaction: CuSO4.5H2O(s) ⇌ CuSO4(s) + H2O(l) ?