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

20. Phenols

Phenol Acidity

Organic Chemistry

20. Phenols

Phenol Acidity

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Multiple Choice

Rank the following molecules in increasing order of acidity (least acidic to most acidic).

I < IV < II < III

I < III < IV < II

V < II < III < I

III < II < IV < I

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Verified step by step guidance

Identify the functional groups attached to the benzene ring in each molecule. Molecule I has a nitro group (NO2) at the para position, Molecule II has a hydroxyl group (OH), Molecule III has both a nitro group (NO2) at the ortho position and a hydroxyl group (OH), and Molecule IV has a tert-butyl group and a hydroxyl group (OH).

Understand the effect of substituents on acidity. The nitro group is an electron-withdrawing group, which increases acidity by stabilizing the negative charge on the conjugate base. The tert-butyl group is an electron-donating group, which decreases acidity.

Consider the position of the nitro group in Molecule III. The ortho position allows for stronger electron-withdrawing effects due to proximity, enhancing the acidity compared to the para position in Molecule I.

Compare the acidity of Molecule II and Molecule IV. Molecule II has only a hydroxyl group, while Molecule IV has a tert-butyl group that decreases acidity. Therefore, Molecule II is more acidic than Molecule IV.

Rank the molecules based on the analysis: Molecule IV is the least acidic due to the electron-donating tert-butyl group, followed by Molecule II with only a hydroxyl group, then Molecule I with a para nitro group, and Molecule III is the most acidic due to the ortho nitro group.