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

4. Alkanes and Cycloalkanes

IUPAC Naming

Organic Chemistry

4. Alkanes and Cycloalkanes

IUPAC Naming

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1:08 minutes

Problem 1a

Textbook Question

Using the general molecular formula for alkanes:
a. Predict the molecular formula of the C₂₈ straight-chain alkane.

Verified step by step guidance

Understand that alkanes are saturated hydrocarbons with the general molecular formula C_nH_2n+2, where n is the number of carbon atoms.

Identify the number of carbon atoms in the given alkane, which is 28 in this case.

Substitute n = 28 into the general formula for alkanes: C_nH_2n+2.

Calculate the number of hydrogen atoms by using the formula 2n + 2. Substitute n = 28 into this expression to find the number of hydrogen atoms.

Combine the number of carbon and hydrogen atoms to write the molecular formula of the C₂₈ straight-chain alkane.

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Key Concepts

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

Alkanes

Alkanes are saturated hydrocarbons consisting entirely of single bonds between carbon atoms and hydrogen atoms. They follow the general molecular formula CnH2n+2, where n is the number of carbon atoms. This formula helps predict the number of hydrogen atoms in a straight-chain alkane.

Straight-Chain Alkanes

Straight-chain alkanes are a type of alkane where carbon atoms are connected in a linear sequence without any branching. This structure affects the molecular formula, as each carbon atom contributes to the overall count of hydrogen atoms according to the alkane formula CnH2n+2.

Molecular Formula Prediction

Predicting the molecular formula involves applying the general formula for alkanes, CnH2n+2, to determine the number of hydrogen atoms in a molecule. For a C28 straight-chain alkane, substituting n=28 into the formula gives C28H58, indicating 28 carbon atoms and 58 hydrogen atoms.

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Related Practice

Textbook Question

What is each compound’s systematic name?

Textbook Question

What is each compound’s systematic name?

Textbook Question

a. There are 18 isomeric alkanes of molecular formula C₈H₁₈. Draw and name any eight of them.

Textbook Question

For each molecular formula, draw all the isomeric alkynes, and give their IUPAC names. Circle the acetylenic hydrogen of each terminal alkyne.

(b) C₆H₁₀ (seven isomers)

Textbook Question

Draw a condensed and a skeletal structure for each of the following:

b. 2,2,5-trimethylhexane

Textbook Question

Make a model of propane (C₃H₈), and draw this model using dashed lines and wedges to represent bonds going back and coming forward.

Textbook Question

Correct the following incorrect names using standard IUPAC nomenclature. [Draw a compound that corresponds to the incorrect name, and then rename it.]

(a) 4-methylhexane

Multiple Choice

Why is it important to use the IUPAC naming system in organic chemistry?

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