Question

Assertion : Coordination number of $Fe$ and Co in $[Fe(C_{2}O_{4})_{3}]^{3-}$ and $[Co(en)_{3}]^{3+}$ respectively is $6$.
Reason : $C_{2}O^{2-}_{4}$ and en (ethane-$1,2$-diamine) are didentate ligands.

• A. If both assertion and reason are true and reason is the correct explanation of assertion
• B. If both assertion and reason are true but reason is not the correct explanation of assertion
• C. If assertion is true but reason is false.
• D. If both assertion and reason are false.

Answer 1

Answer: (A)

$Fe$ atom in $\left[ Fe \left( C _{2} O _{4}\right)_{3}\right]^{3-}$ is surrounded by three bidentate ligands.
There six metal - ligand bonds.
Hence, co-ordination number is $6$ .
Co atom in,$\left[ Co ( en )_{3}\right]^{3+}$ is surrounded by three bidentate ligands. There six metal - ligand bonds.
Hence, co-ordination number is $6$ .
Note: $C _{2} O _{4}^{2-}$ and en (ethane $-1$, 2-diamine) are bidentate ligands.