Question

Balance the equation: Fe + O2 ----> Fe2O3

Please help, this confuses me a lot....

Answer 1

Chemist here!

To balance a chemical equation, start by looking at what you'd have with no coefficients:\[Fe + 2O ---> 2 Fe + 3 O\]Looks like we're short an iron and an oxygen. The first thing to do is increase the amount of iron by one.\[2Fe + 2O ---> 2Fe + 3O\]The iron is balanced now, but there's not enough oxygen. This is a problem, though- oxygen molecules can only provide even amounts of oxygen.

Whenever you run into this odd-even issue, just double the entire reaction:\[some Fe + someO_2 ---> 2Fe_{2}O_{3}\]It then looks like this in the broken-down form:\[4Fe + 4O ---> 4Fe + 6O\]Can you see what to do from there?

Answer 2

Fe2 + O2 -----> Fe2O3
4Fe + 3O2 -----> 2Fe2O3
4 Fe's on reactant side.
6 Oxgens on reactant side
4 iron on product side
6 oxygen on product side