Carbon ii oxide (CO) acts as a reducing agent such that it reduces oxides of less reactive metals in the reactivity series such as lead, copper and zinc. Therefore a reaction between carbon ii oxide and iron ii oxide will be; Fe2O3 (s) + 3CO (g) = 3CO2 (g) + 2Fe (s) The mass of 35 g of Fe contains 0.625 moles ( 35 g ÷56 g) Using the mole ratio of CO : Fe which is 3:2 , we can get the number of mole of CO needed, That is 0.625 × 3/ 2 = 0.9375 moles Therefore, 0.9375 moles are required, but 1 mole of CO = 28 g, the mass of CO required will therefore be 0.9375 × 28 = 26.25 g thus 26.25 g of CO are needed
