Reaction of iron nails with copper sulphate
solution in water. The world around us is made up of matter.
With the planet constantly undergoing changes, there are changes in look and composition
of the matter itself. Scientists have divided these changes in matter
into two categories; physical and chemical changes.
A physical change is a change in the appearance or physical properties of a substance and
it does not produce a new substance. For example, Melting of ice-cream is a physical change.
A chemical change is a change that creates a new substance. The burning of paper is a
good example of a chemical change. The aim of this experiment is to carry out
the reaction between iron nail and copper sulphate solution in water and classify it
as a physical or chemical change. Materials Required
Copper sulphate solution, Iron nails, boiling tubes, stands with clamp and a piece of thread.
Procedure Take two stands with clamps and fix one test
tube in each stand. Pick one of the iron nails from the watch
glass, tie it with a piece of thread and hang it in one of the boiling tubes.
Then tie the other end of the thread to the stand.
Take copper sulphate solution in a beaker and pour some of it into both the boiling
tubes. Keep the apparatuses undisturbed for a day.
After one day, remove the iron nail immersed in the solution and place it in the watch
glass. Compare the two iron nails placed in the watch
glass. Iron nail placed in the watch glass show greyish
colour of iron whereas the iron nail dipped in the copper sulphate solution shows a brown
coating. This indicates that copper is deposited on
the iron nail by displacing iron. The colour of the copper sulphate solution
in which the iron nail was dipped changes from blue to green whereas the colour of the
copper sulphate solution in the other test tube remains the same.
The change of colour from blue to green of the solution in which the iron nail was dipped
indicates a chemical change in which copper has been displaced by iron from the copper
sulphate solution and a new compound FeSO4 is formed.
i.e. CuSO4 (aq) + Fe (s) ->FeSO4 (aq) + Cu(s) Copper sulphate Iron Ferrous sulphate Displaced
copper deposited over nails Precautions
Try to avoid touching the copper sulphate solution and the nail dipped in the copper
sulphate solution. It is better to wear gloves while using materials
containing copper sulphate.