Question

How many moles of fe2o3 will be produced from 18.0 g of fe assuming o2 is available in excess

Answer 1

Answer:

0.161 moles

Explanation:

Given parameters:

Mass of Fe  = 18g

Unknown:

Number of moles of Fe₂O₃  = ?

Solution:

To solve this problem, we have to work from the known to the unknown specie.

One cogent point we need to take from this problem is that oxygen gas is in excess. The Fe reacting is therefore the limiting reactant which implies that it will determine the extent of the reaction.

Now, the known specie is Fe;

  The balanced reaction equation is shown below;

                  4Fe    +   3O₂      →    2Fe₂O₃

Proceed to find the number of moles of Fe given;

        Number of moles of Fe = $\frac{mass}{molar mass}$

                  Molar mass of Fe  = 56g/mol

        Number of moles of Fe  = $\frac{18}{56}$   =  0.32mole

From the balanced reaction equation;

            4 moles of Fe produced 2 moles of Fe₂O₃

          0.32 moles of Fe will produce $\frac{0.32 x 2}{4}$    = 0.161 moles of  Fe₂O₃