Page 17 - Curriculum Visions Dynamic Book

EQUATION: Iron oxide reduced by carbon monoxide
Iron oxide + carbon monoxide ➪ iron metal + carbon dioxide Fe2O3(s) + 3CO(g) ➪ 2Fe(l) + 3CO2(g)
catalyst: a substance that speeds up a chemical reaction but itself remains unaltered at the end of the reaction.
oxidation/reduction: a reaction in which oxygen is gained/lost.
Carbon monoxide as a reducing agent
This laboratory demonstration shows how carbon monoxide can act as a reducing agent, taking oxygen from a metal ore. It is an example of a refining technique widely used in industry.
The glass tube contains black copper oxide. Carbon monoxide gas is blown through the tube, and the surplus is ignited and burns with a blue flame from a small hole in the tube.
Notice how the copper changes to an orange colour. The heat of the Bunsen burner is speeding up the reaction of the carbon monoxide with the copper oxide, producing carbon dioxide gas and leaving pure copper behind.
The way that carbon monoxide takes up oxygen can also be used in industry to refine metal. A blast furnace, used to produce iron from iron ore, uses coke and air to produce the carbon monoxide and the heat needed to release the iron from its ore.
 Carbon monoxide is passed over the black copper oxide powder (copper ore) in a test tube. The glowing surface shows where the reaction between copper oxide and carbon monoxide is occurring. As the carbon monoxide exits the tube it is burnt giving a characteristic blue flame.
 The reduced copper oxide changes colour as the oxygen is removed.
The material left is pure copper.
EQUATION: Reduction of copper
Copper oxide + carbon monoxide ➪ carbon dioxide + copper
CuO(s) + CO(g) ➪ CO2(g) + Cu(s) heat
17
17