CHEM 120 Lecture Notes - Lecture 27: Proton-Exchange Membrane, Magnesium Oxide, Lithium Battery

• School: McGill University
• Department: Chemistry
• Course: CHEM 120
• Professor: Laura Pavelka

Document Summary

Cell potential in voltaic cells is positive, electrons flow from anode to cathode. Activity series of metals: ranks metals by strength as a reducing agent, or their ability to. Metal activity is another way of classifying redox strength, just particularly looking at metals. Tin: oxidation: s sn2+ + 2e- ; reduction: 2h+ + 2e- h2: overall: sn(s) + 2h+(aq) sn2+(aq) + h2(s) (e = 0. 14v) Weakest reducing agents: can"t reduce water nor acid (cannot displace h2 from h+ or. H2o) ; least active ; metals that lie above the reduction of h+ in standard electrode potentials table (see image) Metals displacing metals: more active metals can displace less active metal ions from solution (reduce it back to solid) ex. Na and zn: are both moderate, can reduce at least acids, but when mixed together this is what happens: Strong oxidizing agents (high electronegativity) form weak reducing agents. Strong reducing agents (low electronegativity) form weak oxidizing agents.