Question

50 ml of solution and 10.1g Mg is combined. Which has reacted with 50 ml solution of 10.5g O2 combined, Your actual is 11.9g of MgO. What is your Theoretical Yield?

Answer 1

2 Mg + O2 -------------> 2MgO

2 moles of magnesium react with 1 mole of oxygen to form 2 moles of MgO

Molecular weight of Magnesium = 24.3

10.1 gm of magnesium used = 0.415 mol

Molecular weight of Oxygen = 16

10.5 gm of oxygen used = 0.656 mol

Molecular weight of MgO = 40.3

Here limiting reagent used is Magnesium as 2 moles of Magnesium is required for 1 mole of oxygen and hence 0.328 moles of oxygen will be required

Therefore

48.6 gm of Magnesium gives 80.6 gm of MgO

10.1 gm of Mg will give how much MgO

Amount of MgO produced = (10.1*80.6)/48.6 = 16.75 gm

Theoratical yield of MgO = 16.75 gm