Examine the following half-reactions and select the strongest oxidizing agent among the species listed.

cr 2+(aq) + 2e- = cr (s) e= -0.913 v
fe 2+(aq) + 2e- = fe (s) e= -0.447 v
sr 2+(aq) + 2e- = sr (s) e= -2.89 v
co 2+(aq) + 2e- = co (s) e= -0.28 v

a. co 2+(aq)
b. fe (s)
c. fe 2+ (aq)
d. sr 2+ (aq)
e. cr 2+ (aq)

a. Co²⁺(aq)

Explanation:

The standard potential in a redox reaction (E) allows  the classification of different substances according to their oxidizing and reducing power.

For the reactions:

Cr²⁺(aq) + 2e⁻ = Cr(s) E= -0.913 V

Fe²⁺(aq) + 2e⁻ = Fe(s) E= -0.447 V

Sr²⁺(aq) + 2e⁻ = Sr(s) E= -2.89 V

Co²⁺(aq) + 2e⁻ = Co(s) E= -0.28 V

If the standard potential for the reaction is positive, the reaction will occur spontaneously. As these reactions are of reductions, the more positive E will be the strongest oxidizing agent. For that reason the right answer is:

a. Co²⁺(aq)

I hope it helps!

the energy to form plasma comes from heat or electricity in the atmosphere!

sunny~ ☺

first one is the correct answer