Table of contents

1. Matter and Measurements4h 31m
2. Atoms and the Periodic Table5h 23m
3. Ionic Compounds2h 18m
4. Molecular Compounds2h 18m
5. Classification & Balancing of Chemical Reactions3h 17m
6. Chemical Reactions & Quantities2h 27m
7. Energy, Rate and Equilibrium3h 46m
8. Gases, Liquids and Solids3h 25m
9. Solutions4h 10m
10. Acids and Bases3h 29m
11. Nuclear Chemistry56m
BONUS: Lab Techniques and Procedures1h 38m
BONUS: Mathematical Operations and Functions47m
12. Introduction to Organic Chemistry1h 34m
13. Alkenes, Alkynes, and Aromatic Compounds2h 12m
14. Compounds with Oxygen or Sulfur1h 6m
15. Aldehydes and Ketones1h 1m
16. Carboxylic Acids and Their Derivatives1h 11m
17. Amines39m
18. Amino Acids and Proteins1h 51m
19. Enzymes1h 37m
20. Carbohydrates1h 41m
21. The Generation of Biochemical Energy2h 8m
22. Carbohydrate Metabolism2h 22m
23. Lipids2h 26m
24. Lipid Metabolism1h 45m
25. Protein and Amino Acid Metabolism1h 37m
26. Nucleic Acids and Protein Synthesis2h 54m

1. Matter and Measurements

Physical & Chemical Changes

GOB Chemistry

1. Matter and Measurements

Physical & Chemical Changes

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Multiple Choice

Which of the following represents a reversible change?

Melting a chocolate bar then re-solidifying it in the freezer.

Changing water vapor into oxygen and hydrogen gas.

Turning a potato into french fries.

Baking a cake from a recipe.

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Verified step by step guidance

Understand the concept of reversible changes: A reversible change is a physical change that can be undone, meaning the original substance can be recovered in its original form.

Identify the processes involved in each option: Melting and re-solidifying, chemical decomposition, physical transformation, and chemical reaction.

Analyze the melting and re-solidifying of a chocolate bar: Melting is a physical change where the chocolate changes from solid to liquid, and re-solidifying is the reverse process, making it reversible.

Consider the decomposition of water vapor: Changing water vapor into oxygen and hydrogen gas involves breaking chemical bonds, which is a chemical change and not easily reversible.

Evaluate the transformation of a potato into french fries and baking a cake: Both involve chemical changes (cooking processes) that alter the original substances, making them irreversible.