In a #10*g# mass of an iron oxide there are #4*g# of iron. How many grams of oxygen are there?

1 Answer
Oct 2, 2016

Answer:

If I have #£10-00# and I give you #£4-00#, then how many pounds do I have left?

Explanation:

You have formed #10*g# of an oxide of iron; this could #FeO#, or #Fe_2O_3# or a mixed valence oxide. The point is that the constituent atoms are the metal and oxygen. If the iron content is #4*g# then surely there must be a #6*g# mass of oxygen.