Four unknown metals W, X, Y and Z show the following properties: (i) Metal W displaces X from its aqueous nitrate solution. (ii) Metal Y displaces W from its aqueous nitrate solution. (iii) Metal Z does not displace X from its aqueous nitrate solution. The correct increasing order of standard reduction potentials of these metals is:

Step-by-step solution

A metal with a lower standard reduction potential (stronger reducing agent) can displace a metal with a higher standard reduction potential from its aqueous salt solution. From (i), W displaces X, meaning W is a stronger reducing agent than X. Thus, E^ _ W From (ii), Y displaces W, meaning Y is a stronger reducing agent than W. Thus, E^ _ Y From (iii), Z does not displace X, meaning Z is a weaker reducing agent than X. Thus, E^ _ Z > E^ _ X . Combining these inequalities, the increasing order of standard reduction