Question

Calculate the number of moles of oxygen required to produce 240 g of mgo by burning mg metal. (atomic mass mg = 24, o = 16)

Answer 1

Answer: 3 moles

Explanation: The chemical equation for the reaction is

Mg+1/2O2 —›MgO

Molar mass of MgO =24+16=40

No.of moles of MgO = 240/40=6moles

According to the balanced chemical equation 1 mole of O2 is required to produce 2 mole of MgO

There for No.of moles of O2 is required to produce 6 mole of MgO = 3moles