Samples of four metals A, B, C and D were taken and were added to the following solutions one by one.
The results obtained have been tabulated as follows :
`{:("Metal",,"Solution to which metal is added",,),(,"Iron(II) sulphate","Copper(II) sulphate","Zince sulphate","Silver nitrate"),("A","No reaction","Displacement"," __"," __"),("B","Displacement"," __","No reaction"," __"),("C","No reaction","No reaction","No reaction","Displacement"),("D","No reaction","No reaction","No reaction","No reaction"):}`
Use the table given above to answer the following questions :
(a) Which is the most reactive metal ?
(b) What would you observe when B is added to solution of copper(II) sulphate ?
(c ) Arrange the metals A, B, C and D in order of increasing reactivity.

Explanation

Metal A is more reactive than copper and less reactive than iron.
Metal B is more reactive than iron and less reactive
than Zinc.
Metal C is more reactive than silver only and less reactive than other metals.
Metal D is the least reactive in nature.
n the light of above information, we can conclude that
(a) Metal B is the most reactive.
Since B is more reactive than iron, it is also more reactive than copper. This means that it would displace copper from copper (II) sulphate solution.
The blue colour of solution will slowly fade.
(c) The decreasing order of reactivity of metals is: `B gt A gt C gt D`.