MnO4-(aq) + I-(aq) → MnO2(aq) + IO3-(aq) Balance the reaction that occurs in a basic environment: MnO4-(aq) + I-(aq) → MnO2(aq) + IO3-(aq) +7 -1 +4 +5 3e- + 4H+(aq)+ MnO4-(aq) → MnO2(aq) + 2H2O(l) 2 3H2O(l) + I-(aq) → IO3-(aq) + 6H+(aq) + 6e- 2OH-(aq) + 2H2O(l) 2H+(aq) H2O(l) + 2MnO4-(aq) + I-(aq) → 2MnO2(aq) 2MnO2(aq) + H2O(l) + IO3-(aq) + 2OH-(aq)

Al(s) + H2O(l) → Al(OH)4-(aq) + H2 (g) Balance the reaction that occurs in a basic environment: Al(s) + H2O(l) → Al(OH)4-(aq) + H2 (g) Once this is balanced (alphabetically on each side by name of the first element if it’s a compound or polyatomic ion), you will be able to use the coefficients to describe a combination to a safe where bonus points are kept. Once you know the combination, write it down like this: X – XX – XX on the back of an index card that I will give you (with your work on the front) and bring it me. You have one chance to unlock the lock!

Combination to the safe: 2-62-23 Balance the reaction that occurs in a basic environment: Al(s) + H2O(l) → Al(OH)4-(aq) + H2 (g) 2 [ 4H2O + Al → Al(OH)4- + 4H+ + 3e- ] 3 [ 2e- + 2H+ + H2O → H2 + H2O ] _______________________________________ 8H2O + 2Al → 2Al(OH)4- + 3H2 +2H+ 2Al + 6H2O + 2OH- → 2Al(OH)4- + 3H2 Combination to the safe: 2-62-23 (acidic) (basic)