Simply remember OIL RIG. Oxidation Is Loss (of electron) and Reduction Is Gain (of electron). In the case of MnO4-(aq) + 8H+(aq) + 5e- --> Mn2+(aq) + 4H2O(l) H is the oxidizing agent, because it causes Mn to be oxidized to Mn2+.
The oxidation state of magnesium in magnesium hydroxide is +2 no matter what reaction you are looking at.
The Chlorine. Which is being reduced ( accepting electrons )
This is the answer on Apex, +2 is wrong
No, it is not.
Your 10/22 was manufactured in 2008.