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

7. Energy, Rate and Equilibrium

Gibbs Free Energy (Simplified)

GOB Chemistry

7. Energy, Rate and Equilibrium

Gibbs Free Energy (Simplified)

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Multiple Choice

Consider the combustion of butane gas and predict the signs of ΔS, ΔH and ∆G.
C₄H₁₀(g) + 13/2 O₂(g) ⟶ 4 CO₂(g) + 5 H₂O(g)

+ΔS; +ΔH; +∆G

+ΔS; +ΔH; –∆G

+ΔS; –ΔH; –∆G

–ΔS; –ΔH; –∆G

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Verified step by step guidance

Identify the type of reaction: The combustion of butane is an exothermic reaction, which typically releases heat.

Determine the sign of ΔH (enthalpy change): Since the reaction is exothermic, ΔH is negative because heat is released.

Analyze the change in entropy (ΔS): The reaction involves the conversion of gases. There are 6.5 moles of gas on the reactant side (1 mole of C4H10 and 6.5 moles of O2) and 9 moles of gas on the product side (4 moles of CO2 and 5 moles of H2O). Since the number of gas molecules increases, ΔS is positive.

Consider the sign of ΔG (Gibbs free energy change): For a spontaneous reaction at constant temperature and pressure, ΔG is negative. Since the reaction is exothermic (negative ΔH) and has a positive ΔS, ΔG will be negative, indicating spontaneity.

Summarize the signs: The combustion of butane results in +ΔS (increase in entropy), –ΔH (release of heat), and –ΔG (spontaneous process).