Question

In an experiment you have 5 moles of Fe, how many grams of Fe₂O₃ can be produced?

Answer 1

As we can easily observe that $Fe_2O_3$ contains 2 moles of $Fe$ .

Hence 2 mole of $Fe$ $= 1$ mole of $Fe_2O_3$

1 mole of $Fe= \dfrac{1}{2}$ mole of $Fe_2O_3$

5 moles of$Fe=$ $\dfrac{5}{2}$ moles of $Fe_2O_3$

Now:

Weight of $Fe_2O_3$ = moles of $Fe_2O_3 \times$ molar mass of $Fe_2O_3$

Weight of $Fe_2O_3=$ $\dfrac{5}{2} \times 159.69=399.225 gm \approx 400 gm$