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Rank the following in order of decreasing nuclephilicity, putting the most nucle

ID: 1073411 • Letter: R

Question

Rank the following in order of decreasing nuclephilicity, putting the most nucleophilic first. The reaction of teri-butyl bromide, (CH_3)_2 CBr, with ethanol affords the substitution product tert-butyl ethyl ether, (CH_3)_3 COCH_2 CH_3, in acidic conditions. What would happen to the rate of the reaction if the concentration of ethanol was doubled? A) The rate increases by a factor of 2 B) The rate remains the same C) The rate decreases by a factor of 2. D) The rate increases by a factor of 4. What is the direction of equilibrium when acetylene (C_2 H_2) reacts with H_2 N^- in an acid-base reaction? A) Left B) Right C) Neither D) Cannot be determined

Explanation / Answer

30. Conjugate base is always a better nuceophile. So, CH3O- > CH3OH and CH3S- > CH3SH

More the electronegativity of donor, lesser the nucleophilic strength, Hence combining these two factors, D is the correct answer as charged ion is more nucleophilic than the neutral molecule.

31. Being tertiary halide, it undergoes SN1 reaction i.e. the rate of the reaction depends only on concentration of substrate(Tertiary bromide and not on Ethyl alcohol). Hence B is the correct option.

32. It moves right initiallyand then equilibrium is reached.