Displacement reactions

A more reactive metal will displace (take the place of) a less reactive metal in a solution of its salt.

REACTING IRON WITH COPPER SULPHATE SOLUTIONRESULTSappearance of copper sulphate solutionBLUE SOLUTIONappearance of iron filingsGREY FILINGSinitial temperature (dc)20/20.5/21 final temperature (dc)29appearance of productsRED SOLUTION AND A PALE GREEN SOLUTION

ExplanationIron is a more reactive metal than copper and so displaces it from the solution of copper sulphate.Iron +copper sulphate=copper+ iron(III)sulphate.

ADDING SILVER NITRATE SOLUTION TO COPPER WIRECopper is a more reactive metal than silver so it displaces silver from the solution.

Displacement from metal oxidesA more reactive metal will displace a less reactive metal from its heated oxide. Reduction means loss of oxygen from a compound Oxidation means addition of oxygen to an element.

Thermit reaction: Displacement of iron from iron oxide using aluminiumMethodThe magnesium strip was ignited. This led into a mixture of aluminium and iron oxide.ResultsAfter about 3 seconds, there was a bright light. The aluminium burnt with an orange flame. The product was a white powder.ConclusionAluminium is a more reactive metal than iron and will displace it.This reaction is highly exothermic (hence description "Thermit reaction") It produces enough heat to melt the iron produced. It is also used to weld railway lines.

Carbon and hydrogen in the activity seriesCarbon and hydrogen are 2 non-metals in the activity series. C is between Al and Zn.H is between Ph and CuCarbon will displace any metal below it (below Al).Hydrogen will displace any metal below it (below Ph).

Displacement using carbon or hydrogenBoth of these non-metals are used to displace a less reactive metal in order to get the metal.Since C+H2 bring about reduction of the oxides, they are called: "reducing agents".Carbon is a very good reducing agent.

EXPERIMENT. TO REDUCE COPPER OXIDE WITH CARBON.ResultsWhen the mixture was heated, it glowed red. When we put the mixture into the water, it shot out the carbon. The test tube broke and we could see red lumps of copper in it.CONCLUSIONThe mixture was put into water to stop the carbon from reacting with oxygen.

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