KCET2014ChemistryAldehydes and Ketones
The correct arrangement for the ions in the increasing order of their radii is
Options
- A( Ca ²⁺, K ⁺, S ²⁻ )
- B( Ol ⁻, F ⁻, S ²⁻ )
- C( Na ⁺, Cl ⁻, Ca ²⁺ )
- D( N a⁺, A l³⁺, B e²⁺ )
Correct answer
A. ( Ca ²⁺, K ⁺, S ²⁻ )
Step-by-step solution
The number of electrons and the group number of the given species are given below: array |l|l|l|l|l| Ions & At. No & Group & Period & No. of e⁻ s S²⁻ & 16 & 16 & 3 & 18 K⁺ & 13 & 1 & 4 & 18 C a²⁺ & 20 & 2 & 4 & 18 array There ions are isoelectronic, therefore ( S²⁻ ) have greater size due to higher effective nuclear charge ( (Z_ eff ) ) followed by ( K ⁺ )then ( Ca ²⁺ ) Hence, the correct order of decreasing ionic radii is ( Ca ²⁺ < K ⁺ < S ²⁻ )