Predict the major, organic product for the following reaction. <img src="https://media.pearsoncmg.com/ph/esm/ecs_mullins_organic1e/msa/content/practice-test/img/Ch10_Q05_QT.jpg" alt="The figure illustrates a reaction in which the product has to be determined. The reaction contains two reactants. The first reactant has the following structure: A 5-carbon pentagonal ring is in a vertical orientation with C 1 occupying the topmost vertex. C 2 is single bonded to C 2 of a 4-carbon alkyne chain depicted as a line structure using 2 zigzag lines from C 1 to C 3 and 3 parallel lines between C 3 and C 4. C 2 of the alkyne chain is single bonded to C H 3 on the upper left in the form of a line. The second reactant is H 2 written over the reaction arrow. P d over C is written under the reaction arrow." />

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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

9. Alkenes and Alkynes

Hydrogenation of Alkynes

Organic Chemistry

9. Alkenes and Alkynes

Hydrogenation of Alkynes

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Multiple Choice

Predict the major, organic product for the following reaction.

The figure illustrates the structure of a molecule. A 5-carbon pentagonal ring is in a vertical orientation with C 1 occupying the topmost vertex. C 2 is single bonded to C 1 of a 3-carbon alkene chain depicted as a line structure using 2 zigzag lines. In the alkene chain, a double bond is present between C 2 and C 3. C 1 of the alkene chain is single bonded to C H 3 on the upper left and C H 3 on the upper right, each in the form of a line.

The figure illustrates the structure of a molecule. A 6-carbon hexagonal ring is in a vertical orientation with C 1 occupying the topmost vertex. C 1 is single bonded to C H 3 on the upper right and C H 3 on the upper left, each in the form of a line. C 2 is double bonded to C H 2 in the form of two parallel lines.

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Verified step by step guidance

Identify the functional group in the starting material. The structure contains an alkyne group, which is a carbon-carbon triple bond.

Recognize the reagents used in the reaction. The reaction involves hydrogen gas (H₂) and a palladium on carbon (Pd/C) catalyst, which is typically used for hydrogenation reactions.

Understand the reaction type. The presence of H₂ and Pd/C suggests a catalytic hydrogenation reaction, which will convert the alkyne to an alkane by adding hydrogen atoms across the triple bond.

Predict the product. In a complete hydrogenation of an alkyne, two equivalents of hydrogen are added, converting the triple bond into a single bond, resulting in an alkane.

Draw the major organic product. Replace the alkyne group in the starting material with a single bond, adding hydrogen atoms to each carbon that was part of the triple bond, resulting in a saturated hydrocarbon.