Table of contents

1. Intro to General Chemistry3h 48m
2. Atoms & Elements4h 16m
3. Chemical Reactions4h 10m
4. BONUS: Lab Techniques and Procedures1h 38m
5. BONUS: Mathematical Operations and Functions48m
6. Chemical Quantities & Aqueous Reactions3h 53m
7. Gases3h 49m
8. Thermochemistry2h 37m
9. Quantum Mechanics2h 58m
10. Periodic Properties of the Elements3h 9m
11. Bonding & Molecular Structure3h 29m
12. Molecular Shapes & Valence Bond Theory1h 57m
13. Liquids, Solids & Intermolecular Forces2h 23m
14. Solutions3h 1m
15. Chemical Kinetics2h 53m
16. Chemical Equilibrium2h 29m
17. Acid and Base Equilibrium5h 1m
18. Aqueous Equilibrium4h 47m
19. Chemical Thermodynamics1h 50m
20. Electrochemistry2h 42m
21. Nuclear Chemistry2h 36m
22. Organic Chemistry5h 7m
23. Chemistry of the Nonmetals2h 39m
24. Transition Metals and Coordination Compounds3h 16m

1. Intro to General Chemistry

Classification of Matter

General Chemistry

1. Intro to General Chemistry

Classification of Matter

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Multiple Choice

Which of the following is a mixture?

NaCl

Air

H2O

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Verified step by step guidance

Step 1: Understand the difference between a pure substance and a mixture. A pure substance has a fixed composition and distinct properties, while a mixture contains two or more substances physically combined, each retaining its own properties.

Step 2: Identify the nature of each option: NaCl (sodium chloride) is an ionic compound, O2 (oxygen) is a diatomic molecule, and H2O (water) is a molecular compound. All three are pure substances with fixed compositions.

Step 3: Recognize that air is a combination of different gases such as nitrogen, oxygen, carbon dioxide, and others, physically mixed together without chemical bonding, making it a mixture.

Step 4: Conclude that among the options, air is the only mixture because it consists of multiple components physically combined, unlike the other pure substances listed.

Step 5: Remember that mixtures can be homogeneous (uniform composition, like air) or heterogeneous (non-uniform composition), and air is an example of a homogeneous mixture.