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

Rate of Reaction

GOB Chemistry

7. Energy, Rate and Equilibrium

Rate of Reaction

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1:12 minutes

Problem 47a

Textbook Question

For the reaction C(s, diamond) → C(s, graphite), ∆G = -0.693 kcal/mol (-2.90 kJ/mol) at 25 °C.
a. According to this information, do diamonds spontaneously turn into graphite?

Verified step by step guidance

Understand the role of a catalyst: A catalyst lowers the activation energy of both the forward and reverse reactions equally, without affecting the overall thermodynamic properties such as ∆G (Gibbs free energy).

Identify the activation energy change for the forward reaction: The activation energy decreases from 28.0 kcal/mol to 23.0 kcal/mol, which is a reduction of 5.0 kcal/mol.

Apply the principle of microscopic reversibility: Since the catalyst affects both the forward and reverse reactions equally, the activation energy for the reverse reaction will also decrease by the same amount, 5.0 kcal/mol.

Calculate the new activation energy for the reverse reaction: Subtract the same reduction (5.0 kcal/mol) from the original activation energy of the reverse reaction. To find the original activation energy of the reverse reaction, use the relationship between the forward and reverse activation energies and the ∆G of the reaction.

Use the relationship: Activation energy (reverse) = Activation energy (forward) + ∆G (in kcal/mol). Substitute the values to determine the original reverse activation energy, then subtract 5.0 kcal/mol to find the new activation energy for the reverse reaction.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Activation Energy

Activation energy is the minimum energy required for a chemical reaction to occur. It represents the energy barrier that reactants must overcome to transform into products. A catalyst lowers the activation energy, allowing the reaction to proceed more easily and quickly, but it does not change the overall energy difference between reactants and products.

Gibbs Free Energy (∆G)

Gibbs Free Energy is a thermodynamic potential that measures the maximum reversible work obtainable from a thermodynamic system at constant temperature and pressure. A negative ∆G indicates that a reaction is spontaneous in the forward direction. The value of ∆G is related to the equilibrium position of the reaction and helps predict the favorability of both forward and reverse reactions.

Catalysis and Reaction Direction

Catalysis refers to the process of increasing the rate of a reaction by adding a substance (catalyst) that is not consumed in the reaction. While a catalyst lowers the activation energy for both the forward and reverse reactions, it does not affect the Gibbs Free Energy change (∆G) of the reaction. Therefore, if the activation energy for the forward reaction decreases, the activation energy for the reverse reaction will also decrease by the same amount.

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