Matthew S. answered 11/14/14
Tutor
4.9
(59)
General and Organic Chemistry Tutoring
First off, you are missing the arrow in the above reaction, it should be as follows:
3 H2C2O4 + 2 HNO3 -> 2 NO + 6 CO2+ 4 H2O
To answer this question, I would first draw out the molecules. The oxidation states of the C and N can be found by counting the number of bonds they have with oxygen. This should give you the following oxidation states for C and N:
+3 +5 +2 +4
3 H2C2O4 + 2 HNO3 -> 2 NO + 6 CO2+ 4 H2O
The C increased from +3 to +4 in oxidation state, so it was the element oxidized.
The N decreased from +5 to +2, so it was reduced.
HNO3 oxidized H2C2O4, so HNO3 is the oxidizing element.
H2C2O4 reduced HNO3, so H2C2O4 is the reducing agent.