I'm assuming that by "miles" you mean moles.
If O2 is the excess reactant, that means Fe is the limiting reactant. That means that the amount of product being formed depends on the amount of Fe reactant present. To calculate the moles of Fe2O3 formed, start with the given 6.4 moles of Fe and use the mole to mole ratio given by the reaction as shown below:
6.4 mol Fe x

=
3.2 mol Fe2O3
Given :
Number of molecules of
.
To Find :
How many moles are in given number of molecules.
Solution :
We know, in 1 moles of any element/compound contains
at atoms/molecules.
So, number of moles in
molecules are :

Therefore, number of moles are 8.97 .
Any of the basic mechanical devices for applying a force, such as an inclined plane, wedge, or lever.