Determine whether which of the following redox reactions will occur spontaneously in the forward direction? a) Ni(s) + Zn 2+ (aq) → Ni 2+ (aq) + Zn(s) b) Fe(s) + Pb 4+ (aq) → Fe 2+ (aq) + Pb(s) c) Al(s) + Ag + (aq) → Al 3+ (aq) + Ag(s) d) Pb(s) + Mn 2+ (aq) → Pb 2+ (aq) + Mn(s)

Determine whether which of the following redox reactions will occur spontaneously in the forward direction. So remember, we're going to say that a reaction, a redox reaction, can occur spontaneously if the element that is supposed to be oxidized is oxidized, and the one that is reduced is reduced. So if we take a look here, we have nickel solid plus zinc 2+ion, giving us nickel 2+ion+zincsolid. So nickel here goes from 0 to plus 2, so nickel is being oxidized. And then zinc goes from 2 plus to neutral to 0, so zinc is being reduced. Go and take a look at the activity series chart. So if nickel is truly being oxidized, it should be higher up than zinc is. So if we take a look here, we would see that nickel is not higher up than zinc, so this reaction would not occur, and therefore it's not spontaneous. For the next one, we have iron going from 0 to plus 2, so iron's oxidation number is increasing so it has been oxidized. Lead 4 goes from plus 4 to 0, so it's being reduced. Again, look to see is is iron higher up than lead? If it is, then it can be oxidized. So if we look at the list, we can see here that iron is indeed higher up than lead is, is, so this could occur. Next, we have silver going from 0 to plus 3, so silver now is being oxidized, And then silver, so aluminum is being oxidized, silver goes from plus 1 to 0, so silver is being reduced. So if we take a look here, look at the list, is aluminum higher up than silver is? We're gonna say, yes, in fact, it is. So since since aluminum is higher up than silver, this could also occur. Next we have lead going from 0 to plus 2, so lead is being oxidized. Manganese goes from plus 2 to 0, so manganese is being reduced. For this to happen, lead has to be higher up than manganese, and if you look at the list it is not. So here both b and c could happen spontaneously in the forward direction because what's being reduced is being should be reduced, and what is being oxidized is being oxidized.

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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

5. Classification & Balancing of Chemical Reactions

Spontaneous Redox Reactions

GOB Chemistry

5. Classification & Balancing of Chemical Reactions

Spontaneous Redox Reactions

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Multiple Choice

Determine whether which of the following redox reactions will occur spontaneously in the forward direction?
a) Ni(s) + Zn²⁺(aq) → Ni²⁺(aq) + Zn(s)
b) Fe(s) + Pb⁴⁺(aq) → Fe²⁺(aq) + Pb(s)
c) Al(s) + Ag⁺(aq) → Al³⁺(aq) + Ag(s)
d) Pb(s) + Mn²⁺ (aq) → Pb²⁺(aq) + Mn(s)

Only b)

Both b) and c)

a), b) and c)

Both c) and d)

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Verified step by step guidance

Identify the half-reactions for each redox reaction. For example, in reaction a), the half-reactions are: Ni(s) → Ni2+(aq) + 2e- and Zn2+(aq) + 2e- → Zn(s).

Determine the standard reduction potentials (E°) for each half-reaction from a standard reduction potential table. Note that the more positive the E° value, the greater the tendency for the species to be reduced.

Calculate the standard cell potential (E°cell) for each reaction by using the formula: E°cell = E°(cathode) - E°(anode). The cathode is where reduction occurs, and the anode is where oxidation occurs.

Evaluate the spontaneity of each reaction. A positive E°cell indicates that the reaction is spontaneous in the forward direction.

Compare the calculated E°cell values for each reaction to determine which reactions are spontaneous. Only reactions with positive E°cell values will occur spontaneously in the forward direction.