Choose and best oxidizing agent and the best reducing agent: Ni2+, Al, H+, and I- ???
I'm so confused, please help!
I know the oxidizing agent is being reduced and the reducing agent is getting oxidized. But how do I use the standard reduction potential table? I can't find the right ones??
You do it this way. You're right; the oxidizing agent is reduced and the reducting agent is is oxidized. Oxidation is the loss of electrons and reduction is the gain of electrons. You have two problems so let's separate them.
Here are the two in the problem that can be reduced.
Ni^2+ + 2e ==> Ni Eo = ?
2H^+ + 2e ==> H2 Eo =
Look up those Eo values in the Ered tables. The one with the larger positive Eo value is the most easily reduced (which makes it the stronger oxidizing agent).
Then do the same with the reducing agents. Reducing agents are oxidized and oxidation is the loss of electrons so I'll write these as oxidations.
Al ==> Al^3+ + 3e Eo = ?
2I^- ==> I2 + 2e Eo = ?
You can't look up these equations in the Ered table BUT you can look up the reverse; i.e.,for the Al one you will find Al^3+ + 3e ==> Al. You will find that about -2.8 volts or so (I don't remember the exact number), then turn that equation around to what I have above (written as an oxidation) and change the sign to +2.8 or so. So the I^- the same way. The more positive Eox value will be the stronger reducing agent. Some profs don't like all this switching around. Your teacher may have a different way of doing this.
Now let me complain about the problem I don't know how you are to determine the BEST oxidizing agent or the BEST reducing agen. You can determine the strongest of each as I've outlined above but the BEST one depends upon what your trying to oxidize or reduce. Hope this helps.
To determine the best oxidizing agent and the best reducing agent among the given options (Ni2+, Al, H+, and I-), you can use the standard reduction potential table. This table lists the standard reduction potentials (E°) for various half-reactions, which allows you to compare the tendency of different species to be oxidized or reduced.
When looking at the standard reduction potential table, keep in mind that the more positive the value of E° for a half-reaction, the stronger the oxidizing agent it is, while the more negative the value, the stronger the reducing agent it is.
To use the standard reduction potential table to determine the best oxidizing agent and reducing agent among the given options, follow these steps:
1. Identify the half-reactions: Write down the half-reactions for each species. In this case, the options are Ni2+, Al, H+, and I-. Each species could potentially undergo oxidation or reduction.
2. Locate the half-reactions in the table: Find the reduction half-reactions on the table. If the half-reaction is written as a reduction, you can directly use the E° value from the table. If the half-reaction is written as oxidation, reverse the sign of the E° value to use it.
3. Compare the E° values: Compare the E° values for each half-reaction. The species with the more positive E° value will be the stronger oxidizing agent, while the species with the more negative E° value will be the stronger reducing agent.
4. Determine the best oxidizing agent and the best reducing agent: Based on the comparison of E° values, the species with the more positive E° value is the best oxidizing agent, and the species with the more negative E° value is the best reducing agent.
Now, you can follow these steps using the standard reduction potential table to determine the best oxidizing agent and reducing agent among Ni2+, Al, H+, and I-.
To determine the best oxidizing agent and reducing agent, you can use the standard reduction potential table. The higher the standard reduction potential, the stronger the oxidizing agent, and the lower the standard reduction potential, the stronger the reducing agent.
Let's use the standard reduction potential table:
Standard Reduction Potentials:
Ni2+ + 2e- → Ni (-0.26 V)
Al3+ + 3e- → Al (-1.66 V)
H+ + e- → H2 (0 V)
I2 + 2e- → 2I- (0.53 V)
From the given species, we compare their standard reduction potentials:
- Ni2+ has a standard reduction potential of -0.26 V.
- Al has a standard reduction potential of -1.66 V.
- H+ has a standard reduction potential of 0 V.
- I- has a standard reduction potential of 0.53 V.
Since Ni2+ has a higher standard reduction potential than Al, H+, and I-, it is the best oxidizing agent.
For the reducing agent, we look for the species with the lowest standard reduction potential. In this case, Al has the lowest standard reduction potential (-1.66 V), making it the best reducing agent.
So, the best oxidizing agent is Ni2+ and the best reducing agent is Al.