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Negative and positive electrode potentials

Answer Text:
Negative and positive electrode potentials:
(a). Negative electrode potential
- If the metal electrode has a higher/ greater tendency to loose electrons than the hydrogen electrode; then the electrode is negative
with respect to hydrogen electrode; and its electrode potential is negative.
Examples: Zinc, Magnesium etc.
(b). Positive electrode potential
- If the tendency of an electrode to loose electrode is lower than the hydrogen electrode, then the electrode is positive with respect to the hydrogen
electrode; and its potential is positive.
Examples: copper, silver etc
Reduction potentials
- Is a standard electrode potential measured when the electrode in question is gaining electrons.
- The lower the tendency of an electrode to accept/ gain electrons; the lower (more negative) the reduction potential and vice versa.

- Thus potassium ions with E #theta#= -2.92V have a lesser tendency to gain electrons than magnesium ions.
- Thus Potassium is the weakest oxidizing agent; but the strongest reducing agent, since it has the greatest tendency to donate electrons.
Note:
- Oxidation potentials will be the potentials of electrodes measured when they are losing electrons hence undergoing oxidation.