Question

A student added few pieces of aluminium metal to two test tubes A and B containing aqueous solutions of iron sulphate and copper sulphate. In the second part of her experiment, she added iron metal to another test tubes C and D containing aqueous solutions of aluminium sulphate and copper sulphate.
In which test tube or test tubes will she observe colour change? On the basis of this experiment., state which one is the most reactive metal and why?

Answer 1

the test tubes are A,B and D.
colour change also In A,B and D

Answer 2

Answer: There will be color change in A, B and D testy tube. Aluminium is the most reactive metal.

Explanation: 1) A:  $2Al+3FeSO_4\rightarrow (Al)_2(SO_4)_3+3Fe$

This reaction will take place as aluminium is more reactive than iron as it loses electrons readily than iron.Thus there will be a color change.

B: $2Al+3CuSO_4\rightarrow (Al)_2(SO_4)_3+3Cu$

This reaction will take place as aluminium is more reactive than copper as it loses electrons readily than copper.Thus there will be a color change.

2) C: $3Fe+(Al)_2(SO_4)_3\rightarrow 3FeSO_4+2Al$

This reaction will not take place as iron is less reactive than aluminium as it cannot lose electrons more readily than aluminium.Thus there will be no color change.

D:  $Fe+CuSO_4\rightarrow FeSO_4+Cu$

This reaction will take place as iron is more reactive than copper as it loses electrons readily than copper.Thus there will be a color change.

Aluminum is the most reactive metal as it lies higher in the reactivity series as it can easily lose electrons as compared to iron and copper.