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

13. Alcohols and Carbonyl Compounds

Oxidizing and Reducing Agents

Organic Chemistry

13. Alcohols and Carbonyl Compounds

Oxidizing and Reducing Agents

Previous problemNext problem

Problem 5a

Textbook Question

Calculate the oxidation numbers for the indicated atoms.
a.

Verified step by step guidance

Identify the structure of the starting material. The image shows a benzene ring with a side chain, which is likely a primary alcohol or an aldehyde, given the context of oxidation reactions.

Recognize the oxidizing agent. In this case, H₂CrO₄ (chromic acid) is a strong oxidizing agent commonly used to oxidize primary alcohols to carboxylic acids and secondary alcohols to ketones.

Determine the oxidation state of the carbon atom in the side chain before the reaction. If the side chain is a primary alcohol (R-CH₂OH), the carbon attached to the OH group is in the -1 oxidation state.

Predict the product of the reaction. H₂CrO₄ will oxidize the primary alcohol to a carboxylic acid (R-COOH), changing the oxidation state of the carbon from -1 to +3.

Calculate the change in oxidation number for the carbon atom. The change from -1 to +3 indicates an increase in oxidation state, confirming that oxidation has occurred.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above

Play a video:

Was this helpful?

Key Concepts

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

Oxidation Numbers

Oxidation numbers are a way to keep track of electrons in atoms as they undergo chemical reactions. They represent the hypothetical charge an atom would have if all bonds were ionic. In organic chemistry, oxidation numbers help determine how electrons are transferred in reactions, especially in redox processes. For example, in the reaction with H2CrO4, identifying the oxidation state of carbon atoms in the benzene ring is crucial.

Chromic Acid (H2CrO4) as an Oxidizing Agent

Chromic acid (H2CrO4) is a strong oxidizing agent commonly used in organic chemistry to oxidize alcohols to ketones or carboxylic acids. It works by increasing the oxidation state of carbon atoms, typically converting primary alcohols to carboxylic acids and secondary alcohols to ketones. Understanding its role in the reaction helps predict the changes in oxidation numbers of the involved atoms.

Benzene Ring Structure

The benzene ring is a stable, aromatic hydrocarbon with a hexagonal structure and alternating double bonds. Its stability is due to resonance, where electrons are delocalized over the ring. In reactions, the benzene ring can influence the reactivity of attached groups, such as the side chain in the given structure. Recognizing the benzene ring's properties is essential for understanding how it affects the oxidation process in the reaction.

Watch next

Master General Features of Redox with a bite sized video explanation from Johnny

Start learning