Question

Which half-reaction is most easily oxidized?

Answer 1

Answer:

The half-reaction Na⁺ + e⁻ ⇒ Na with E°=-2.71 V is most easily oxidized.

Explanation:

Oxidation-reduction reactions or redox reactions are those in which an electron transfer occurs between the reagents. An electron transfer implies that there is a change in the number of oxidation between the reagents and the products.

The gain of electrons is called reduction and the loss of electrons oxidation. That is to say, there is oxidation whenever an atom or group of atoms loses electrons (or increases its positive charges) and in the reduction an atom or group of atoms gains electrons, increasing its negative charges or decreasing the positive ones.

The species that supplies electrons is the reducing agent (that is, it is that species that oxidizes, yielding electrons and increasing its positive charge, or decreasing the negative one causing the reduction of the other species) and the one that gains them is the oxidizing agent ( that is, it is that species that is reduced, capturing electrons and increasing its negative charge, or decreasing its positive charge, causing oxidation of the other species).

Electron donors are called reducers; Electron acceptors are called oxidants.

The potential for reduction is the tendency of chemical species in a redox reaction to acquire electrons, that is, it has a tendency to reduce. The potential is a physical quantity that, in the International System, is measured in volts (V). Reference is made to hydrogen, which is assigned a potential equal to zero.  The reduction potentials are generally evaluated under standard conditions, this is at a concentration of 1 M in the case of solutes in solution and 1 atm for gases.

Then, the semi-reaction that has the greatest potential for reduction will be the one to reduce.

And the semi-reaction that has the lowest potential for reduction will be the one that oxidizes.

Finally, the half-reaction Na⁺ + e⁻ ⇒ Na with E°=-2.71 V is most easily oxidized.

Answer 2

The answer is Na+ + e-  Na = -2.71 V