Question

Juana Scott monitored the rate of the reaction of sodium ethoxide with 2-bromo-2-methyl hexane and with 2-fluoro-2-methyl hexane, respectively in hexane (CH..). The reactions were carried out in two different solvents and at two different concentrations as shown in the table below. King James inspired by the work of JS tried the reaction of 2-Bromobutane and 2-fluorobutane with sodiusethoxide under similar reaction conditions used by Dr. Scott. JS EXPT. + X = Br X = Br X-Br X - Br {R-X) 0.1 M 0.1 M 0.2 M 0.1 M 0.1 M 0.1 M {Nackt 0.1 M 0.1 M 0.1 M 0.2 M 0.1 M 0.1 M Solvent Hexane Formic acid Formic acid Formic acid formic acid Hexane Rate 10/sec 2000/sec 4000/sec 2000/sec 200/sec 100/sec X - F KJ EXPT. {R-X) X-Br 0.1 M x - Br 0.1 M X - Br 0.2 M X = Br 0.1 M X - F 0.1 M 0.1 M {NaOet) 0.1 M 0.1 M 0.1 M 0.2 M 0.1 M 0.1 M Solvent Hexane Formic acid Hexane Hexane Hexane Formic acid Rate 5000/sec 0.1/sec 20000/sec 20000/sec 4950/sec 0.09/sec 1. Which chemist will report an effect of the leaving group on the rate of the reaction? (a) JS (b)- KJ (c) Both (d) Neither 2. Whose reaction is likely a second order reaction? (a) JS (b) KJ (c) Both (d) Neither Whose experiment was independent of the concentration of sodium? (a) JS (b) KJ (c) Both (d) Neither Whose experiment probed the influence of the nucleophile? (a) JS (b) KJ (c) Both (d) Neither Whose experiment most probably gave optical rotation of -10°c? (a) JS (b) KJ (c) Both (d) Neither Whose experiment will be favored if done in ethanol as a solvent? (a) JS (b) KJ (c) Both (d) Neither The rate constant for JS's reaction is? 6. 7.

Answer 1

Solution 1.

Both will report the effect of leaving group on the rate of reaction.

Reason : In Js experiment by considering 1and 6 experiment we can observe the change in date of reaction when only the leaving group in changing only while other parameter are being constant.

Similarly in KJ experiment

By 8 and 13 experiment it is clear that by changing the leaving group rate of reaction is also changing.