JEE Main201910 Apr 2019Evening ShiftChemistryCoordination CompoundsActual
The incorrect statement is.
Options
- AThe spin-only magnetic moments of F e H 2 O 6 2 + and C r H 2 O 6 2 + are nearly similar.
- BThe spin-only magnetic moment of N i N H 3 4 H 2 O 2 2 + is 2.83   B M .
- CThe gemstone, ruby, has C r 3 + ions occupying the octahedral sites of beryl.
- DThe color of C o C l N H 3 5 2 + is violet as it absorbs the yellow light.
Correct answer
C. The gemstone, ruby, has C r 3 + ions occupying the octahedral sites of beryl.
Step-by-step solution
A   F e H 2 O 6 2 + ,   F e 2 + → 3 d 6 → 4 unpaired electron C r H 2 O 6 2 + ,   C r 2 + → 3 d 4 → 4 unpaired electron B   N i N H 3 4 H 2 O 2 2 + = N i 2 + → 3 d 8 → 2 unpaired electron μ m = 2.83   B . M C In gemstone, ruby has C r 3 + ion occupying the octahedral sites of aluminium oxide A l 2 O 3 normally occupied by A l 3 + ion. D Complimentary color of violet is yellow.