MCQ
Which of the following ligand is ambidentate
- A$NO_3^-$
- ✓$C_2S_2O_2^{2-}$
- C$SO_4^{2-}$
- D$CO_3^{2-}$
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Reason $(R)$ : Oxygen forms $\mathrm{p} \pi-\mathrm{p} \pi$ multiple bonds with itself and other elements having small size and high electronegativity like $\mathrm{C}, \mathrm{N}$, which is not possible for sulphur.
In the light of the above statements, choose the most appropriate answer from the options given below :
$(i)\,\,(CH_3)_2CH - CH_2Br \xrightarrow{{{C_2}{H_5}OH}}$ $ (CH_3)_2CH - CH_2OC_2H_5 + HBr$
$(ii)\,\,(CH_3)_2CH - CH_2Br \xrightarrow{{{C_2}{H_5}O^-}} $ $(CH_3)_2CH - CH_2OC_2H_5 + Br^-$
The mechanisms of reactions $(i)$ and $(ii)$ are respectively