Question

6. (12 pts) Answer the following questions regarding the Sn2 reaction. a. What is the significance of the 'S', 'N', and '2' in the name of the Sn2 reaction? (2 pts) b. Give the rate law for the Sn2 reaction (2 pts) C. Based on the rate law, how would reducing reaction volume from 20 mL to 10 mL affect the rate of an SN2 reaction? (2 pts) (circle one) no effect twice as fast 4 times as fast half as fast as fast d. Predict the fastest and slowest reaction. (4 pts) (0(CH3)3CBr + CH3 hzon (CH3)3COCH3 + Br® (1) (CH3),CHBr + Ⓡochz DMSO, (CH3)2CHOCH3 + Biº (II) (CH3)2CHBr + och; CH3OH (CH3)2CHOCH3 + Bo® (iv) CH3CH2Br + OCH, DMSO CH3CH2OCH3 + Br e. Briefly describe the two factors that were most important in deciding which reaction in part d was the fastest. (2 pts)

Answer 1

Solution =

solution it ① S² reaction robens this reaction take place on both the reactant substitution(s) nucleophilicon bi molecular (12) in single step. Here rate depends and nucleophile. Reactant & Nucleophile - preoduct Rate = k[ Reactant [Nucleophile] hon reaction volume is reduced from 20m) to 10ml mookkeet on the rate of reaction. since change in volume has an equal elkect on the concentreations ok reactants and ok products, so it has an e eksect on backward and forward reate and tem system the remains remains at at equillibro equilli brium, But in that ase no ok moles must be equal on both side

① (CH3) z C Bre + 8cu, enzon ₃ (CH3), COCH3 + Bro This is slowest reaction. Because methoxi de can't the tertiary carbon due to steric reepulsion caused methyl group. attack by threee Oh Cha Br + OCH3 - CH₂ CH₂ OCH 3 Bro this reaction is kastest. The alkyl halide is primary ,so methoxide attack and Bro is leaving from the carbon. Here no. steric repulsion between nucleophile (cho) and reactant. - CH₂ C_Br thou - (CH3)3C- ochz CH2 X (slowest CH₂ - CHp For A och - CH₂ CH - O - CH₂ (fashest) o o steric koctar strength of nucleophile leaving group