Answer:
We will expect 4 moles of MgO to be formed (option b).
Explanation:
Step 1: The balanced equation
2Mg + O2 → 2MgO
Step 2: Data given
Number of moles of Magnesium = 4 moles
Oxygen = in excess → this means Magnesium is the limiting reactant
Magnesium will completely be consumed ( 4 moles). There will remain 0 moles.
For 2 moles of magnesium consumed, we need 1 mole of oxygen to produce 2 moles of MgO.
For 4 moles of magnesium, we need 4/2 = 2 moles of oxygen.
For 4 moles of magnesium, we will produce 4/1 = 4 moles of MgO
We will expect 4 moles of MgO to be formed (option b).
it should either be 5 or 10
