- AC−F
- BC−Cl
- CC−Br
- DC−I
Explanation:
As we progress down the periodic table from fluorine to iodine, molecular size increases.
As a result, we also see an increase in bond length. Conversely, as molecular size increases and we get longer bonds, the strength of those bonds decreases.
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Statement I: Both $\left[\mathrm{Co}\left(\mathrm{NH}_3\right) 6\right]^{3+}$ and $\left[\mathrm{CoF}_6\right]^3$ complexes are octahedral but differ in their magnetic behaviour.
Statement II: $\left[\mathrm{Co}\left(\mathrm{NH}_3\right)\right]^{3+}$ is diamagnetic whereas $\left[\mathrm{CoF} \mathrm{F}_6\right]^{3-}$ is paramagnetic.
In the light of the above statements, choose the correct answer from the options given below:
