In the structure of the dichromate ion, there is a :
(A)non-linear unsymmetrical Cr−O−Cr bond.
(B)non-linear symmetrical Cr−O−Cr bond.✓ Correct
(C)linear symmetrical Cr−O−Cr bond.
(D)linear unsymmetrical Cr−O−Cr bond.
Answer: (B)
Solution
The dichromate ion is built from two CrO4 tetrahedra joined through one shared, bridging oxygen. The two Cr−O bridge bonds are of equal length because the charge is delocalised equally over both halves, so the bridge is symmetrical, while the Cr−O−Cr angle is about 126∘, so the bridge is bent. The dichromate ion contains a non-linear symmetrical Cr−O−Cr bridge.
JEE Main · 2021 · 31 Aug 2021 · Shift 1 · Single correct option
