Q2 / 54 · JEE Advanced 2018 (Paper 1) · Chemistry
The correct statement(s) regarding the binary transition metal carbonyl compounds is (are) (Atomic numbers: )
- ATotal number of valence shell electrons at metal center in is 16
- Correct answerBThese are predominantly low spin in nature
- Correct answerCMetal - carbon bond strengthens when the oxidation state of the metal is lowered
- DThe carbonyl bond weakens when the oxidation state of the metal is increased
Solution
Complexes have 18- electrons in their valence shell
Carbonyl complexes are predominantly low spin complexes due to strong ligand field
As electron density increases on metals (with lowering oxidation state on metals), the extent of synergic bonding increases. Hence M - C bond strength increases
While positive charge on metals increases and the extent of synergic bond decreases and hence C - O bond becomes stronger.
Carbonyl complexes are predominantly low spin complexes due to strong ligand field
As electron density increases on metals (with lowering oxidation state on metals), the extent of synergic bonding increases. Hence M - C bond strength increases
While positive charge on metals increases and the extent of synergic bond decreases and hence C - O bond becomes stronger.
Hence, the correct answer is options: 'B', 'C'.