In the reaction 2mg (s) + o2 (g) + 2h2o (l) → 2mg2+ (aq) + 4oh– (aq), how many electrons are transferred? a. 0 b. 1 c. 2 d. 3 e. none of the above (this is not a redox reaction.)

F. None of the above (Four electrons are transferred).

2Mg → 2Mg^(2+) + 4e^(-)

O_2 + 2H_2O + 4e^(-) → 4OH^(-)

2Mg + O_2 + 2H_2O + 4e^(-) → 2Mg^(2+) + 4OH^(-) + 4e^(-)

2Mg + O_2 + 2H_2O → 2Mg^(2+) + 4OH^(-)

This is a redox reaction in which two atoms of Mg transfer four electrons to one molecule of O_2.