The leaving group is that functional group which is ejected with `overline e^, s` of the `sigma` -bond in a reaction. Better the leaving group, faster is the reaction. The relative leaving ability of the leaving group `X` in `(R - X)` is increased by : (i) The polarisability of `(R - X)` bond. (ii) The stability of `X^(Ө)`. (iii) The degree of stabilisation through solvation of `X`. (iv) The strength of `(R - X)` bond. The leaving group tendency is also called fugacity. Which statement is wrong ?A. In polar aprotic solvents such as `DMSO, DMF`, and `DMA`, the fugacity order is `I^(Ө) gt Br^(Ө) gt Cl^(Ө) gt F^(Ө)`.B. Strong bases are good leaving groups.C. The leaving group order of the following is : `overset (Ө) OH gt RO^(Ө) gt CH -= C^(Ө) gt overset (Ө) NH_2`.D. Charges species are good leaving groups than neutral species.

The leaving group is that functional group which is ejected with `over

1.	The leaving group is that functional group which is ejected with `overline e^, s` of the `sigma` -bond in a reaction. Better the leaving group, faster is the reaction. The relative leaving ability of the leaving group `X` in `(R - X)` is increased by : (i) The polarisability of `(R - X)` bond. (ii) The stability of `X^(Ө)`. (iii) The degree of stabilisation through solvation of `X`. (iv) The strength of `(R - X)` bond. The leaving group tendency is also called fugacity. Which statement is wrong ?A. In polar aprotic solvents such as `DMSO, DMF`, and `DMA`, the fugacity order is `I^(Ө) gt Br^(Ө) gt Cl^(Ө) gt F^(Ө)`.B. Strong bases are good leaving groups.C. The leaving group order of the following is : `overset (Ө) OH gt RO^(Ө) gt CH -= C^(Ө) gt overset (Ө) NH_2`.D. Charges species are good leaving groups than neutral species.
Answer» Correct Answer - B Weak bases are good leaving groups. Acidic order : `H_2 O gt ROH gt CH -= CH gt NH_3` Basic order : `overset (Ө) O H lt R O^(Ө) lt CH -= C^(Ө) lt overset (Ө) N H_2` Weaker the base, better is the leaving group. Leaving group order : `overset (Ө) O H gt RO^(Ө) gt CH -= C^(Ө) gt overset (Ө) N H_2`.

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