Oxidation and Reduction Reactions REDOX Rxns video clip

Oxidation and Reduction Reactions (REDOX Rxns) video clip Redox Rxns: oxidation-reduction rxns transfer e–’s LEO says GER

REDOX: • transfer e– Oxidation: Reduction: • gain e– • lose e– • charge ↑ • charge ↓ 0 0 0 00 – 2 +3 +3 – 2 4 Fe(s) + 3 O 2(g) → 2 Fe 2 O 3(s)

Metals: tend to be oxidized (lose e–) Nonmetals: tend to be reduced (gain e–) magnesium 0 0 magnesium sulfide sulfur 0 0 +2 – 2 Mg(s) + S(s) → Mg. S(s)

Metals: tend to be oxidized (lose e–) Nonmetals: tend to be reduced (gain e–) LEO says GER 0 0 +2 – 2

-4 +1 0 +4 -2 +1 -2 CH 4(g) + O 2(g) → CO 2(g) + H 2 O(g) Oxidized? (charge ↑) Reduced? (charge ↓)

+2 -1 +1 -1 +2 -1 2 Na. F(aq) + Ca. Cl 2(aq) → 2 Na. Cl(aq) + Ca. F 2(s) Oxidized? (charge ↑) Reduced? (charge ↓) NOT REDOX because… NO charges changed (NO – e loss or gain)

Redox in Living Systems Photosynthesis O– 2 is oxidized to O 20 +4 – 2 +1 – 2 0 6 CO 2 + 6 H 2 O → C 6 H 12 O 6 + 6 O 2 C+4 is reduced to C 0

Redox in Living Systems Cellular Respiration C 0 is oxidized to C+4 0 +1 – 2 0 +4 – 2 +1 – 2 C 6 H 12 O 6 + 6 O 2 → 6 CO 2 + 6 H 2 O O 0 is reduced to O– 2

Quick Quiz! 1. During oxidation, an element _______ electrons. During reduction, an element ____ electrons. A. B. C. D. gains, loses, gains, donates gains, accepts

Quick Quiz. 2. Which element is reduced in the following chemical reaction? +3 – 2 +2 – 2 0 +4 – 2 Fe 2 O 3 + 3 CO 2 Fe + 3 CO 2 A. B. C. D. O Fe C none (not redox)