I dont quite understand how to find out if it's capable of reducing/oxidizing. My understanding is we check each potential and identify which is reduce = highest potential, oxidize = lowest potential.
These are my predictions:
yes
Is Fe2+(aq) capable of reducing VO2+(aq)?
yes
Is Sn metal capable of reducing Fe3+(aq) to Fe2+(aq)?
no
Is H2(g) capable of reducing Ni2+(aq)?
no
Is Cr3+(aq) capable of oxidizing Fe2+(aq)?
yes
Is Fe2+(aq) capable of reducing Sn2+(aq) to Sn metal?
no
Is Fe2+(aq) capable of reducing Cr3+(aq) to Cr2+(aq)?
I do them this way. It would have been helpful for you to include how you came to the conclusions you did AS WELL AS to list the Eo values you looked up. Here is one I've done for you.
Is Fe2+(aq) capable of reducing Sn2+(aq) to Sn metal?
If Sn2+ + 2e ===> Sn (a reduction) then you know
Fe2+ ==> Fe3+ + e because that is an oxidation. So look up the Eo
potentials. For Sn2+ +2e ==> Sn(s) I find Eo red = -0.14
..................For Fe^2+ ==> Fe^3+ + e I find Eo ox = -0.77 (note I looked up the Fe3+ + e ==> Fe2+ to get Eo red of 0.77 then changed the sign.
Now add them together but DON'T multiply the E values by anything.
Sn2+ +2e ==> Sn(s) Eo red = -0.14
Fe^2+ ==> Fe^3+ + e Eoox = -0.77
Sn2+ + 2e + 2Fe2+ ==> Sn(s) + 2Fe^3+ + 2e Eo cell = -0.14 + (-0.77) = -0.91 v for the cell. This cell will NOT go spontaneously so Sn^2+ will NOT reduce the Fe^2+ . You must obtain a + cell value for the cell to work. I find it easy to add the Ered value to the Eo oxd value. If you get a + E value you know the reaction is spontaneous. If you get a - E value you know the reaction is not spontaneous. You know of course to make sure that one half rxn must have electrons on one side and the other half reaction must have electrons on the opposite side. Also, to make the equation accurate you must multiply the half reactions to make the electrons on one side equal to the number on the other side; however, you do NOT multiply the E values. Hope this helps.
Well, let's see if I can help clarify this for you. When it comes to determining if a substance is capable of reducing or oxidizing another substance, we look at their respective reduction potentials. The substance with the higher reduction potential is capable of reducing the substance with the lower reduction potential, while the substance with the lower reduction potential is capable of oxidizing the substance with the higher reduction potential.
Now, let's go through your predictions:
1. Is Fe2+(aq) capable of reducing VO2+(aq)? - Yes, because Fe2+ has a higher reduction potential than VO2+.
2. Is Sn metal capable of reducing Fe3+(aq) to Fe2+(aq)? - Yes, because Sn metal has a higher reduction potential than Fe3+.
3. Is H2(g) capable of reducing Ni2+(aq)? - No, because H2(g) has a lower reduction potential than Ni2+.
4. Is Cr3+(aq) capable of oxidizing Fe2+(aq)? - Yes, because Cr3+ has a higher reduction potential than Fe2+.
5. Is Fe2+(aq) capable of reducing Sn2+(aq) to Sn metal? - No, because Sn2+ has a higher reduction potential than Fe2+.
6. Is Fe2+(aq) capable of reducing Cr3+(aq) to Cr2+(aq)? - No, because Cr3+ has a higher reduction potential than Fe2+.
I hope this clears things up for you! If not, I can always juggle some more information for you.
To determine if a species is capable of reducing or oxidizing another species, you can compare the standard reduction potentials (E°) of the two half-reactions involved.
1. For the first prediction, Fe2+ (aq) reducing VO2+ (aq):
- Look up the standard reduction potentials for the two half-reactions:
- Fe3+ (aq) + e- → Fe2+ (aq) E° = +0.771 V
- VO2+ (aq) + 2H+ (aq) + e- → VO2+ (aq) + H2O E° = +1.02 V
- The higher the value of E°, the better the species is at undergoing reduction. In this case, VO2+ (aq) has a higher E°, so it can be reduced by Fe2+ (aq). Therefore, your prediction is correct: YES, Fe2+ (aq) is capable of reducing VO2+ (aq).
2. For the second prediction, Sn metal reducing Fe3+ (aq) to Fe2+ (aq):
- Look up the standard reduction potentials for the two half-reactions:
- Sn2+ (aq) + 2e- → Sn (s) E° = -0.14 V
- Fe3+ (aq) + e- → Fe2+ (aq) E° = +0.771 V
- The higher the value of E°, the better the species is at undergoing reduction. In this case, Fe3+ (aq) has a higher E°, so it cannot be reduced by Sn metal. Therefore, your prediction is incorrect: NO, Sn metal is not capable of reducing Fe3+ (aq) to Fe2+ (aq).
3. For the third prediction, H2 (g) reducing Ni2+ (aq):
- Look up the standard reduction potentials for the two half-reactions:
- Ni2+ (aq) + 2e- → Ni (s) E° = -0.25 V
- 2H+ (aq) + 2e- → H2 (g) E° = 0.00 V
- The higher the value of E°, the better the species is at undergoing reduction. In this case, Ni2+ (aq) has a higher E°, so it cannot be reduced by H2 (g). Therefore, your prediction is correct: NO, H2 (g) is not capable of reducing Ni2+ (aq).
4. For the fourth prediction, Cr3+ (aq) oxidizing Fe2+ (aq):
- Look up the standard reduction potentials for the two half-reactions:
- Fe3+ (aq) + e- → Fe2+ (aq) E° = +0.771 V
- Cr3+ (aq) + 3e- → Cr (s) E° = -0.74 V
- The higher the value of E°, the better the species is at undergoing reduction. In this case, Cr3+ (aq) has a lower E°, so it cannot oxidize Fe2+ (aq). Therefore, your prediction is correct: NO, Cr3+ (aq) is not capable of oxidizing Fe2+ (aq).
5. For the fifth prediction, Fe2+ (aq) reducing Sn2+ (aq) to Sn metal:
- Look up the standard reduction potentials for the two half-reactions:
- Sn2+ (aq) + 2e- → Sn (s) E° = -0.14 V
- Fe3+ (aq) + e- → Fe2+ (aq) E° = +0.771 V
- The higher the value of E°, the better the species is at undergoing reduction. In this case, Sn2+ (aq) has a higher E°, so it can be reduced by Fe2+ (aq). Therefore, your prediction is incorrect: NO, Fe2+ (aq) is not capable of reducing Sn2+ (aq) to Sn metal.
6. For the sixth prediction, Fe2+ (aq) reducing Cr3+ (aq) to Cr2+ (aq):
- Look up the standard reduction potentials for the two half-reactions:
- Cr3+ (aq) + 3e- → Cr (s) E° = -0.74 V
- Fe3+ (aq) + e- → Fe2+ (aq) E° = +0.771 V
- The higher the value of E°, the better the species is at undergoing reduction. In this case, Cr3+ (aq) has a lower E°, so it cannot be reduced by Fe2+ (aq). Therefore, your prediction is correct: NO, Fe2+ (aq) is not capable of reducing Cr3+ (aq) to Cr2+ (aq).
Remember, these predictions are based on standard reduction potentials and assume standard conditions. In reality, there may be other factors to consider that affect the feasibility of the reactions.
To determine if a substance is capable of reducing or oxidizing another substance, you can use the concept of reduction potentials, also known as oxidation-reduction potentials or redox potentials. Reduction potential is a measure of the tendency of a substance to gain or lose electrons, and it helps predict the direction of electron transfer in a redox reaction.
The higher the reduction potential, the stronger the tendency of a substance to be reduced (gain electrons), while the lower the reduction potential, the stronger the tendency of a substance to be oxidized (lose electrons).
To answer your questions, you will need to compare the reduction potentials of the substances involved in each reaction. Here's how you can do it:
1. Look up the reduction potentials for the given substances in a standard reduction potential table. These tables provide the reduction potentials for various chemical species.
2. Identify the substances involved in the redox reaction (the substance you want to determine if it can reduce/oxidize and the substance you want to determine if it can be reduced/oxidized).
3. Compare the reduction potentials for the substances involved. The substance with the higher reduction potential has a greater tendency to be reduced, while the substance with the lower reduction potential has a greater tendency to be oxidized.
Let's analyze your predictions using this approach:
1. Is Fe2+(aq) capable of reducing VO2+(aq)?
- Compare the reduction potentials of Fe2+ and VO2+. If the reduction potential of Fe2+ is higher than that of VO2+, then Fe2+ is capable of reducing VO2+.
2. Is Sn metal capable of reducing Fe3+(aq) to Fe2+(aq)?
- Compare the reduction potentials of Sn and Fe3+. If the reduction potential of Sn is higher than that of Fe3+, then Sn is capable of reducing Fe3+.
3. Is H2(g) capable of reducing Ni2+(aq)?
- Compare the reduction potentials of H2 and Ni2+. If the reduction potential of H2 is higher than that of Ni2+, then H2 is capable of reducing Ni2+.
4. Is Cr3+(aq) capable of oxidizing Fe2+(aq)?
- Compare the reduction potentials of Cr3+ and Fe2+. If the reduction potential of Cr3+ is higher than that of Fe2+, then Cr3+ is capable of oxidizing Fe2+.
5. Is Fe2+(aq) capable of reducing Sn2+(aq) to Sn metal?
- Compare the reduction potentials of Fe2+ and Sn2+. If the reduction potential of Fe2+ is higher than that of Sn2+, then Fe2+ is capable of reducing Sn2+.
6. Is Fe2+(aq) capable of reducing Cr3+(aq) to Cr2+(aq)?
- Compare the reduction potentials of Fe2+ and Cr3+. If the reduction potential of Fe2+ is higher than that of Cr3+, then Fe2+ is capable of reducing Cr3+.
With this approach, you should be able to assess the capability of each substance to reduce or oxidize another substance based on the reduction potentials.