Table of contents

1. A Review of General Chemistry5h 5m
2. Molecular Representations1h 14m
3. Acids and Bases2h 46m
4. Alkanes and Cycloalkanes4h 17m
5. Chirality3h 39m
6. Thermodynamics and Kinetics1h 22m
7. Substitution Reactions1h 48m
8. Elimination Reactions2h 30m
9. Alkenes and Alkynes2h 9m
10. Addition Reactions3h 19m
11. Radical Reactions1h 58m
12. Alcohols, Ethers, Epoxides and Thiols2h 42m
13. Alcohols and Carbonyl Compounds2h 17m
14. Synthetic Techniques1h 26m
15. Analytical Techniques:IR, NMR, Mass Spect7h 3m
16. Conjugated Systems6h 13m
17. Ultraviolet Spectroscopy51m
18. Aromaticity2h 34m
19. Reactions of Aromatics: EAS and Beyond5h 1m
20. Phenols55m
21. Aldehydes and Ketones: Nucleophilic Addition4h 56m
22. Carboxylic Acid Derivatives: NAS2h 51m
23. The Chemistry of Thioesters, Phophate Ester and Phosphate Anhydrides1h 10m
24. Enolate Chemistry: Reactions at the Alpha-Carbon1h 53m
25. Condensation Chemistry2h 9m
26. Amines1h 43m
27. Heterocycles2h 0m
28. Carbohydrates5h 53m
29. Amino Acids4h 20m
30. Peptides and Proteins2h 42m
31. Catalysis in Organic Reactions1h 30m
32. Lipids 2h 50m
33. The Organic Chemistry of Metabolic Pathways2h 52m
34. Nucleic Acids1h 32m
35. Transition Metals6h 14m
36. Synthetic Polymers1h 49m

7. Substitution Reactions

SN2 Reaction

Organic Chemistry

7. Substitution Reactions

SN2 Reaction

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6:30 minutes

Problem 5

Textbook Question

Write the rate law for the following reaction and identify which molecules are present in the rate-determining step. Draw a possible transition state and propose a mechanism.

Verified step by step guidance

Identify the rate-determining step (RDS): The rate-determining step is the slowest step in the reaction mechanism. Analyze the reaction mechanism provided (if available) to determine which step is the slowest. If no mechanism is given, assume the RDS involves the reactants explicitly mentioned in the rate law.

Write the rate law: The rate law is determined by the molecularity of the rate-determining step. For example, if the RDS involves one molecule of A and one molecule of B, the rate law would be \( \text{Rate} = k[A][B] \). Use the stoichiometry of the RDS to write the rate law.

Identify the molecules in the RDS: Based on the rate law, identify which reactants or intermediates are involved in the rate-determining step. These are the species whose concentrations affect the reaction rate.

Draw a possible transition state: The transition state represents the highest energy point along the reaction coordinate for the RDS. Sketch a structure showing partial bonds and charges to represent the transition state. For example, if the RDS involves a bond-breaking and bond-forming process, show the bonds as partially formed or broken.

Propose a mechanism: Based on the rate law and the transition state, propose a plausible stepwise mechanism for the reaction. Include all intermediates, reactants, and products, ensuring that the mechanism is consistent with the observed rate law and the overall reaction.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Rate Law

The rate law of a chemical reaction expresses the relationship between the reaction rate and the concentration of reactants. It is typically formulated as rate = k[A]^m[B]^n, where k is the rate constant, and m and n are the orders of the reaction with respect to reactants A and B. Understanding the rate law is crucial for predicting how changes in concentration affect the speed of the reaction.

Rate-Determining Step

The rate-determining step (RDS) is the slowest step in a reaction mechanism that controls the overall reaction rate. It is often the step with the highest activation energy and can be identified by analyzing the rate law. The molecules involved in the RDS are directly related to the rate law, as they influence how quickly the reaction proceeds.

Transition State Theory

Transition state theory posits that during a chemical reaction, reactants form a high-energy transition state before converting into products. This transition state represents a point of maximum energy along the reaction pathway and is crucial for understanding reaction mechanisms. Drawing a possible transition state involves illustrating the arrangement of atoms at this critical point, which helps visualize how bonds are formed and broken.

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