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QJEEAdv08Ch2c33: JEE Advanced 2008 Chemistry - Class 12 JEEAdv08Ch2c33 Solution: Both [Ni(CO) ] and [Ni(CN) ] are diamagnetic. They…

Both [Ni(CO) 4_4 ] and [Ni(CN) 4_4 ] 2−^{2-} are diamagnetic. They hybridisations of nickel in these complexes, respectively, are :

Multiple Choice Options

  • A sp 3^3 , sp 3^3
  • B sp 3^3 , dsp 2^2
  • C dsp 2^2 , sp 3^3
  • D dsp 2^2 , dsp 2^2

Step-by-Step Verified Solution

In [Ni(CO) 4_4 ], Ni is in 0 oxidation state, so there are 8 electrons in 3d subshell and 2 electrons in 4s. CO is the strong ligand, so it cause pairing of electrons in 3d subshell leaving one d subshell vacant. Now, the electron from s shell shifts to d creating vacant space in s subshell and thus the hybridisation is sp 3^3 .

Ni(28) = [Ar] 4s 2^2 3d 8^8

IIT-JEE 2008 Paper 2 Offline Chemistry - Coordination Compounds Question 10 English Explanation 1

CO is a strong ligand, causes coupling.

IIT-JEE 2008 Paper 2 Offline Chemistry - Coordination Compounds Question 10 English Explanation 2

In [Ni(CN) 4_4 ] 2−^{2-} , Ni is in +2 oxidation state so it has 8 electrons in d subshell and CN is also a strong ligand which pairs with d subshell atom and leaves one d orbital empty and thus its hybridisation is dsp 2^2 .

In [Ni(CN) 4_4 ] 2−^{2-} , the oxidation state of Ni is +2

Ni 2+^{2+} = [Ar] 3d 8^8 4s 0^0

IIT-JEE 2008 Paper 2 Offline Chemistry - Coordination Compounds Question 10 English Explanation 3

CN −^- is strong ligand, causes coupling.

IIT-JEE 2008 Paper 2 Offline Chemistry - Coordination Compounds Question 10 English Explanation 4

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