Question

Iron(III) oxide is formed when iron combines with oxygen in the air. How many grams of Fe2O3 are formed when 16.7 g of Fe reacts completely with oxygen ?

Answer 1

For problems like this, it is crucial that you deal with the chemistry first, before you begin the mathematics portion of this. So, your first step would be to write down the balanced chemical equation for this reaction. Can you do that?

Answer 2

To write down the balanced chemical equation, look at what you are being told:
"\(\color{blue}{iron}~combines~with~\color{red}{oxygen}\)"