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. The Chemical World9m
- The Scientific Method
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2. Measurement and Problem Solving2h 19m
3. Matter and Energy2h 15m
4. Atoms and Elements2h 33m
5. Molecules and Compounds1h 50m
6. Chemical Composition1h 23m
7. Chemical Reactions1h 43m
8. Quantities in Chemical Reactions1h 8m
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10. Chemical Bonding2h 10m
11 Gases2h 7m
12. Liquids, Solids, and Intermolecular Forces1h 11m
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15. Chemical Equilibrium1h 27m
16. Oxidation and Reduction1h 33m
17. Radioactivity and Nuclear Chemistry53m

16. Oxidation and Reduction

Spontaneous Redox Reactions

Introduction to Chemistry

16. Oxidation and Reduction

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 oxidation half-reaction is Ni(s) → Ni²⁺(aq) + 2e⁻ and the reduction half-reaction is Zn²⁺(aq) + 2e⁻ → Zn(s).

Determine the standard reduction potentials (E°) for each half-reaction using a standard reduction potential table. 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°(reduction) - E°(oxidation).

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. The reactions with positive E°cell values will occur spontaneously in the forward direction.