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

Hess's Law

GOB Chemistry

7. Energy, Rate and Equilibrium

Hess's Law

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Multiple Choice

Calculate the ∆H_rxn for

Given the following reactions:

-177.85 kJ

-355.73 kJ

-258.36 kJ

-487.27 kJ

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Verified step by step guidance

Identify the target reaction: ClF (g) + F2 (g) → ClF3 (g). We need to find the ΔHrxn for this reaction using the given reactions.

Use Hess's Law, which states that the total enthalpy change for a reaction is the sum of the enthalpy changes for each step of the reaction. We will manipulate the given reactions to achieve the target reaction.

Reverse the second given reaction: 2 Cl2O (g) + 6 F2O (g) → 4 ClF3 (g) + 4 O2 (g). This changes the sign of ΔH° to -682.8 kJ.

Multiply the third given reaction by 3/2 to match the stoichiometry of F2 in the target reaction: 3 F2 (g) + 3/2 O2 (g) → 3 F2O (g). This scales the ΔHrxn to -272.55 kJ.

Combine the modified reactions to cancel out intermediates and obtain the target reaction. Sum the ΔH values of the modified reactions to find the ΔHrxn for the target reaction.