How many moles of O2 react with 5.75 moles of Fe?

4.3125 moles

Explanation:

The equation for the reaction between Fe and O₂ is given by;

4Fe + 3O₂ → 2Fe₂O₃

Therefore, 4 moles of Fe reacts with three moles of oxygen gas to form 2 moles of Fe₂O₃.

Therefore;

Mole ratio of Fe to O₂ is 4; 3 Moles of O₂ = Moles of Fe * 3/4 Thus, given the number of moles of iron, Fe as 5.75 moles; Moles of Oxygen gas = 5.75 moles * 3/4

= 4.3125 moles

Therefore, moles of oxygen gas that will react will 5.75 moles of Fe will be 4.3125 moles