REACTIONS OF METALS WITH OXYGEN There is a simple experiment to determine how a metal will react with oxygen: Oxygen can be made by heating potassium permanganate in a test tube and allowing the gas to pass through rocksil wool to the preheated metal as shown. Rocksil wool metal Potassium permanganate Heat 2 Heat 1 Different metals react with different intensities. Some like magnesium react very violently giving out a lot of heat and light while others like copper just give a dull glow. The order of metals reacting with oxygen is: Most reactive Least reactive magnesium > aluminium > zinc > iron > tin > lead > copper > mercury Silver and gold do not react. Potassium, sodium and calcium are too reactive to react with oxygen in this way. The equation for a metal reacting with oxygen is: metal + oxygen metal oxide magnesium + oxygen magnesium oxide i.e.