On a camping trip, Marta roasts a marshmallow in the campfire. The marshmallow grows, and then turns black. Marta notices that the roasted marshmallow smells and tastes differently than the uncooked marshmallows. What
change has taken place, and how does Marta know?
A
a chemical change because the marshmallow changed in taste, color and smell
B
no change because the marshmallow is not a new substance
с
only a physical change because the marshmallow changed size
D
a chemical change because the marshmallow only changed in pH level

Answerthe half-reaction having the greatest tendency to occur at the anode:     i₂(aq) + 2e⁻  ⇄ 2i⁻  ;   e = +0.53 v======oxidation occurs at the anode. we must therefore find the half-reaction with the greatest tendency to oxidize.the given values of e are reduction potentials (the form of the half-reactions are of reduction).the lower the reduction potential, the higher the potential to oxidize. the half-cell with the lowest reduction potential will have the greatest tendency to oxidize at the anode.the half-reaction having the greatest tendency must be    i₂(aq) + 2e⁻  ⇄ 2i⁻    e = +0.53 vbecause its reduction potential is the lowest out of the three.