NEET2015ChemistryChemical Bonding and Molecular StructureActual
The charge/size ratio of a cation determines its polarising power. Which one of the following sequences represents the increasing order of the polarising power of the cationic species, K ⁺, Ca ²⁺, Mg ²⁺, Be ²⁺ ?
Options
- AK ⁺ Ca ²⁺ Mg ²⁺ Be ²⁺
- BBe ²⁺ K ²⁺ Ca ²⁺ Mg ²⁺
- CMg ²⁺ Be ²⁺ K ⁺ Ca ²⁺
- DCa ²⁺ Mg ²⁺ Be ⁺ K ⁺
Correct answer
A. K ⁺ Ca ²⁺ Mg ²⁺ Be ²⁺
Step-by-step solution
High charge and small size of the cations increases polarisation. As the size of the given cations decreases as K ⁺ Ca ²⁺ Mg ²⁺ Be ²⁺ Thus, polarising power increases as K ⁺ Ca ²⁺ Mg ²⁺ Be ²⁺