Table of contents

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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

19. Chemical Thermodynamics

Spontaneous vs Nonspontaneous Reactions

General Chemistry

19. Chemical Thermodynamics

Spontaneous vs Nonspontaneous Reactions

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Multiple Choice

Which of the following pairs of reactants will result in a spontaneous redox reaction at 25°C?

Cu(s) + Zn^2+(aq)

Ag(s) + Fe^3+(aq)

Zn(s) + Cu^2+(aq)

Fe(s) + Ag^+(aq)

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Identify the half-reactions for each pair of reactants. For example, for Cu(s) + Zn^2+(aq), the half-reactions are: Cu(s) → Cu^2+(aq) + 2e⁻ and Zn^2+(aq) + 2e⁻ → Zn(s).

Look up the standard reduction potentials (E°) for each half-reaction from a standard reduction potential table. For example, E° for Cu^2+/Cu is +0.34 V and for Zn^2+/Zn is -0.76 V.

Calculate the standard cell potential (E°cell) for each reaction by using the formula: E°cell = E°(cathode) - E°(anode). A positive E°cell indicates a spontaneous reaction.

For each pair, determine which species is reduced (gains electrons) and which is oxidized (loses electrons). The species with the higher reduction potential will be reduced.

Compare the calculated E°cell values for each pair of reactants. The pair with the highest positive E°cell value will result in the most spontaneous redox reaction at 25°C.