Fe2o3 + 5c + 3o2 = 2fe + 5co2
calculate the number of moles of feo2 that would be needed to react exactly with 0.49 mol of o2

0.33 mol of  Fe₂O₃

Explanation:

For the reaction given in the question -

Fe₂O₃ + 5 C + 3O₂ → 2 Fe + 5 CO₂

Balancing the above reaction ,

2Fe₂O₃ + 5 C + 3O₂ → 2 Fe + 5 CO₂

According to the above balanced reaction ,

2 mol of Fe₂O₃ will react with 5 mol of C and 3 mol of O₂ to give 2 mol of Fe and 5 mol of CO₂ .

Hence ,

2 mol of Fe₂O₃ will react with 3 mol of O₂

or ,

3 mol of O₂   2 mol of Fe₂O₃

Using unitary method ,

1 mol of O₂   2 / 3 mol of Fe₂O₃

From the question , for 0.49 mol of O₂ ,

0.49 mol of O₂ 2 / 3 * 0.49 mol of  Fe₂O₃ = 0.33 mol of  Fe₂O₃

the answer is d.) potassium