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

1. A Review of General Chemistry

Atomic Structure

Organic Chemistry

1. A Review of General Chemistry

Atomic Structure

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5:52 minutes

Problem 10b

Textbook Question

A chemistry student drew the following incorrect electron configuration for carbon. (b) Which rule wasn't followed by the student?

Verified step by step guidance

Step 1: Analyze the electron configuration provided in the image. The configuration shows the 1s and 2s orbitals filled correctly, but the 2p orbitals have two electrons paired in one box and the other two boxes are empty.

Step 2: Recall Hund's Rule, which states that electrons must occupy degenerate orbitals (orbitals of the same energy level) singly before pairing occurs. This minimizes electron repulsion and stabilizes the atom.

Step 3: Identify the mistake in the student's drawing. The student paired two electrons in one 2p orbital without first placing one electron in each of the three 2p orbitals.

Step 4: Explain the correct approach. According to Hund's Rule, the correct electron configuration for carbon's 2p orbitals should have one electron in each of the three 2p orbitals before any pairing occurs.

Step 5: Conclude that the rule violated by the student is Hund's Rule, and emphasize the importance of following this rule for accurate electron configurations.

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Key Concepts

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

Aufbau Principle

The Aufbau Principle states that electrons occupy the lowest energy orbitals first before filling higher energy levels. For carbon, which has six electrons, the correct order of filling is 1s², 2s², and then 2p². This principle is fundamental in determining the electron configuration of elements.

Pauli Exclusion Principle

The Pauli Exclusion Principle asserts that no two electrons in an atom can have the same set of four quantum numbers. This means that an orbital can hold a maximum of two electrons, which must have opposite spins. In the provided configuration, if the same orbital is shown with two electrons having the same spin, this principle is violated.

Hund's Rule

Hund's Rule states that electrons will fill degenerate orbitals (orbitals of the same energy) singly before pairing up. In the case of the 2p orbitals for carbon, the correct configuration should show one electron in each of the three 2p orbitals before any pairing occurs. This rule helps minimize electron-electron repulsion and stabilizes the atom.

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a. How many protons do the following species have?

b. How many electrons does each have?

Na⁺
Ar
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Write the electronic configurations of the third-row elements shown in the partial periodic table in Figure 1-6.

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Chlorine exists as one of two isotopes with atomic masses of 34.969 amu (³⁵Cl) and 36.966 amu (³⁷Cl) . Calculate the relative abundance of ³⁵Cl and ³⁷Cl based on the average atomic mass of 35.453 amu.

Textbook Question

Bromine-79 (50.7% abundance) has an atomic mass of 78.918 amu, whereas bromine-81 (49.3% abundance) has an atomic mass of 80.916 amu. From these data, calculate the average atomic mass of bromine that you would expect to see in the periodic table.

Textbook Question

Give the electron configuration of the following elements.

(d) F

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Why do elements in the same group of the periodic table display similar reactivity?

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Choose the larger atom in each pair.

(d) N or S

Textbook Question

Give the electron configuration of the following elements.

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