Group 14 Elements

To solve the problem, we need to identify the incorrect statement about the oxidation states of Group 14 elements.

1. Review of Oxidation States in Group 14:
Group 14 elements include Carbon (C), Silicon (Si), Germanium (Ge), Tin (Sn), and Lead (Pb). They commonly show +4 and +2 oxidation states. The stability of these oxidation states changes down the group due to the inert pair effect.

2. Evaluate Each Option:

• Option 1: "Carbon and Silicon mostly exhibit +4 oxidation state"
  This is correct. C and Si are lighter members and favor the +4 oxidation state.
• Option 2: "Tin in +2 oxidation state is a reducing agent"
  This is correct. Sn(II) can be oxidized to Sn(IV), hence it acts as a reducing agent.
• Option 3: "Lead in +2 oxidation state is a reducing agent"
  This is incorrect. Pb(II) is relatively stable due to the inert pair effect and behaves more like an oxidizing agent than a reducing agent.
• Option 4: "The order of stability of +2 oxidation state is Ge < Sn < Pb"
  This is correct. The stability of the +2 oxidation state increases down the group due to the inert pair effect.

Final Answer:
The incorrect statement is: “Lead in +2 oxidation state is a reducing agent”.

The complex ion exhibits geometrical isomerism. This is because the two ethylenediamine ( ) ligands and the two chloride ( ) ligands can arrange themselves in different spatial orientations, leading to cis-trans isomerism.