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

Physical & Chemical Changes

General Chemistry

1. Intro to General Chemistry

Physical & Chemical Changes

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Multiple Choice

During which of the following events would a chemical change occur?

Ice melting into water

Salt dissolving in water

Water boiling

Iron rusting

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Verified step by step guidance

Understand the difference between physical and chemical changes. A physical change involves a change in the state or appearance of a substance without altering its composition, while a chemical change results in the formation of one or more new substances with different properties.

Examine each event: Ice melting into water is a physical change because it involves a change of state from solid to liquid without altering the chemical composition of H₂O.

Consider the event of salt dissolving in water. This is a physical change as well, because the salt (NaCl) dissociates into ions (Na⁺ and Cl^-) in water, but no new substances are formed.

Analyze the event of water boiling. This is another physical change, as it involves a change of state from liquid to gas (steam) without changing the chemical composition of H₂O.

Evaluate the event of iron rusting. This is a chemical change because iron (Fe) reacts with oxygen (O₂) in the presence of water to form a new substance, iron oxide (Fe₂O₃), which has different properties from the original iron.