Question

You are provided with metals 'A' and 'B' and a blue coloured solution 'C'. Metal 'A' is greyish in colour and is available as granules in pure form. Metal 'B' is attracted by magnet. Both 'A' and 'B' react with compound 'C' and undergo a displacement reaction so that the blue colour of the solution disappears. Identify A, B and C. Also write a balanced reaction of A with C.

Answer 1

The reaction in which reactive metal displace less reactive metal is known as displacement reaction and the reaction in which group of reactants get interchanged are known as double-displacement reactions. When an electron moves from one energy level to another energy level, then the energy of the electron also changes.

Complete step by step solution:
Let us firstly discuss all the compounds given.
Here metal A is greyish in colour and available in granules in pure form, usually Zinc powder also known as zinc granules is a bluish-gray colored, pure metal powder with particle sizes above 9.0µ. It is produced when purified vapors of zinc are condensed. Some of its characteristics are consistent quality, improved yields and quick reaction time. Therefore, $Metal(A)\to Zinc(Zn).$
Here Metal B is attracted by a magnet. The most common metal attracted towards magnet is Iron $(Fe).$ Also in most famous r=displacement reaction of $Fe$ with $Zn$ and the blue colour formation disappears readily. Thus, $Metal(B)\to Iron(Fe).$
Also here the blue colour solution is Copper Sulphate solution, i.e. $CuS{{O}_{4}}$ which clears that metal C is copper, i.e. $Metal(C)\to Copper(Cu).$
As earlier explained metals $Zn$ and $Fe$ are most reactive as compared with $Cu$ , so there will be a displacement reaction.
Therefore the following reaction is given by:
$Z{{n}_{(s)}}+CuS{{O}_{4(aq)}}\to ZnS{{O}_{4(aq)}}+C{{u}_{(s)}}$
$F{{e}_{(s)}}+CuS{{O}_{4(aq)}}\to FeS{{O}_{4(aq)}}+C{{u}_{(s)}}$

Note:
Remember that alkali metals are not stable and very reactive, so they cannot be used in the production of coins. Similarly $Zn$ is more reactive metal than copper so it is not preferred over copper but even though its reactivity is low.