Concept explainers
(a)
Interpretation: The change in the rate of an E2 reaction is to be stated when the concentration of
Concept introduction: E2 type of reaction follows second order kinetics in which the rate depends on both the reactants. The rate law equation for E2 reaction is expressed as,
Answer to Problem 8.11P
The rate of an E2 reaction is tripled when the concentration of alkyl halide is tripled.
Explanation of Solution
E2type of reaction is second order elimination reaction in which the
The rate law equation for E2 reaction is expressed as,
According to the given statement, concentration of alkyl halide is tripled. Hence, the rate of reaction is
Therefore, the rate of the reaction increases by three times when the concentration of
The rate of an E2 reaction is tripled when the concentration of alkyl halide is tripled.
(b)
Interpretation: The change in the rate of an E2 reaction is to be stated when the concentration of base is halved.
Concept introduction: E2 type of reaction follows second order kinetics in which the rate depends on both the reactants. The rate law equation for E2 reaction is expressed as,
Answer to Problem 8.11P
The rate of an E2 reaction is halved when the concentration of base is halved.
Explanation of Solution
E2 type of reaction is second order elimination reaction in which the rate of reaction depends on both the reactants i.e. the alkyl halide and the base.
The rate law equation for E2 reaction is expressed as,
According to the given statement, concentration of base is halved. Hence, the rate of reaction is,
Therefore, the rate of the reaction decreases by half when the concentration of
The rate of an E2 reaction is halved when the concentration of base is halved.
(c)
Interpretation: The change in the rate of an E2 reaction is to be stated when the solvent is changed from
Concept introduction: E2 reactions are usually preferred in
Answer to Problem 8.11P
The rate of an E2 reaction increases when the solvent is changed from
Explanation of Solution
E2 type of reaction is second order elimination reaction in which the rate of reaction depends on both the reactants i.e. the alkyl halide and the base. The choice of solvent for this type of reaction is polar aprotic. DMSO is a polar aprotic solvent and
The rate of an E2 reaction increases when the solvent is changed from
(d)
Interpretation: The change in the rate of an E2 reaction is to be stated when the leaving is changed from
Concept introduction: A leaving group bigger in size is preferred as it leaves easily and fast while a smaller leaving group leaves with difficulty and slow.
Answer to Problem 8.11P
The rate of an E2 reaction is decreased when the leaving group is changed from
Explanation of Solution
E2 type of reaction is second order elimination reaction in which
the rate of reaction depends on both the reactants i.e. the alkyl halide and the base. Iodine is bigger in size as compared to bromine. An atom bigger in size is a good leaving group. Thus, iodine is a better leaving group then bromine. Thus, when
The rate of an E2 reaction is decreased when the leaving is changed from
(e)
Interpretation: The change in the rate of an E2 reaction is to be stated when the base is changed from
Concept introduction: Strong base is more efficient in proton abstraction and hence, it is more preferred in E2 type of reactions.
Answer to Problem 8.11P
The rate of an E2 reaction is decreased when the base is changed from
Explanation of Solution
E2 type of reaction is second order elimination reaction in which the rate of reaction depends on both the reactants i.e. the alkyl halide and the base. A stronger base will facilitate the abstraction of proton and hence will increase the rate of E2 reaction.
The rate of an E2 reaction is decreased when the base is changed from
(f)
Interpretation: The change in the rate of an E2 reaction is to be stated when the the alkyl halide is changed from
Concept introduction: The rate of E2 reaction depends on the halide being used. A halide in which carbon attached to the leaving group has more number of alkyl groups is usually preferred.
Answer to Problem 8.11P
The rate of E2 reaction increases when the alkyl halide is changed from
Explanation of Solution
E2 type of reaction is second order elimination reaction in which the rate of reaction depends on both the reactants i.e. the alkyl halide and the base. A highly substituted product is preferred in E2 reaction as it is more stable. This can be obtained when the carbon attached to the leaving group has more number of alkyl groups. Since
The rate of E2 reaction increases when the alkyl halide is changed from
Want to see more full solutions like this?
Chapter 8 Solutions
ORGANIC CHEMISTRY
- 5. Classify the following reagents as either nucleophiles or electrophiles: Zn2* , CH3NH2 , HS , OH2 , CH3COOH, H2SO4arrow_forward22. Draw all the alkene products that can be prepared in the following E2 reaction. Circle the alkene that you expect to be the major product based on Zaitsev's Rule. Use curved arrows to show how the major product forms. ما "OC(CH) analghaq my2A 16nsiqi UnA 2 ebileria lenims ocation intermediate affect the rate of an El reaction? mainsroom 13 no 101 ws! sbubal .mainsrbM 13 phen Snobia to mzinaroam bevlovni el sisibamish 149arrow_forwardIn both examples below the reactants shown are combined to bring about a nucleophilic substitution (S1, Sy2) and'or elimination (EI, E2) reaction What is the major reaction that takes place in each case? CH, CH, CH,CH,CHCCH, H20 Br NaNg CH,OH CH,CH,CHCH,CH, SN2arrow_forward
- what is the product and mechanism used in this reaction? MsO RA DBU CH₂Cl2 [arrow_forwardThe reaction of 1-bromobutane with sodium hydroxide affords the substitution product butan-1-ol. What would happen to the rate of the reaction if the concentration of both 1-bromobutane and sodium hydroxide were doubled? The rate increases by a factor of 4. The rate decreases by a factor of 2. The rate remains the same. The rate increases by a factor of 2.arrow_forwardThe mechanism proceeds through a first cationic intermediate, intermediate 1. Nucleophilic attack leads to intermediate 2, which goes on to form the final product. In cases that involve negatively charged nucleophile, the attack of the nucleophile leads directly to the product. H. Br + CH3OH Br Intermediate 2 (product) Intermediate 1 In a similar fashion, draw intermediate 1 and intermediate 2 (final product) for the following reaction. OCH3 Cl2 MEOH ĆI racemic mixture Pay attention to the reactants, they may differ from the examples. In some reactions, one part of the molecule acts as the nucleophile. • You do not have to consider stereochemistry. • Draw one structure per sketcher. Add additional sketchers using the drop-down menu in the bottom right corner. Separate intermediate 1 and intermediate 2 using the the dropdown menu. → symbol fromarrow_forward
- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage LearningOrganic Chemistry: A Guided InquiryChemistryISBN:9780618974122Author:Andrei StraumanisPublisher:Cengage Learning