Calcium carbonate + oxygen
After this discovery, people experimented with different methods to extract more metals from their ores. For example copper and tin were re-melted on the fire to produce bronze. This occurred because tin alters the property of copper, so bronze is an alloy of Cu2Sn. However for some metals, extracting them from their ores is much more difficult than this.
Iron is higher in the Reactivity Series than copper and gold and is a reactive metal. It is also difficult to extract from its ore because iron ore needs a higher temperature to smelt than when melting bronze. If the temperature is increased to 1200˚C then cast iron is produced. However this was too brittle as there was too much carbon. Therefore the cast iron was repeatedly heated and hammered until wrought iron was produced. This, although it could be bent to make shapes, was still too soft. As a result this lead to further heating with carbon fuels (charcoal) and rapid cooling. The bellows, which were much more powerful than the first ones that were used to produce copper, were so large that they were powered by water. Finally an early form of steel was produced, which was hard enough for tools. This long process of intense heating, hammering and rapid cooling proves that iron is more difficult to extract from its ore than metals lower in the Reactivity Series, like gold and copper.
Iron and steel were used for the bodies of cars but they had their bad properties. For example, they tended to rust so the iron and steel needed to be protected with paint. This was quite an expensive process so a better metal was required – aluminium. Aluminium was better than iron and steel in the sense that it doesn’t rust, so no paint is needed to protect it, which reduces costs. It is also light enough for the body, engine housing and wings of aircraft and for trains; iron and steel would make aircraft too heavy to leave the ground. Therefore there was a greater demand for aluminium, so it needs to be extracted from its ore.
Aluminium can be extracted from its ore, aluminium oxide. However the process is not as easy as extracting copper and iron from their ores; in fact it is a difficult and expensive process. This is because aluminium is much higher up in the Reactivity Series to gold, copper and iron. To extract aluminium form its ore, electrolysis of aluminium oxide is required. This is where the aluminium ore (aluminium oxide) is heated and electricity is passed through the molten, raw material. As a lot of electricity is necessary to extract the aluminium, a power station is needed. This process of extracting aluminium from its ore, using electrolysis, is therefore very expensive. This process of electrolysis is a more difficult method than those used to extract gold, copper and iron form their ores, which shows that aluminium is more difficult to extract from its ore.
To conclude I can say that metals higher up in the Reactivity Series require more complex and difficult methods to extract them from this ore. This is proven because gold is found native, copper is extracted from its ore with heat and oxygen and iron requires a much larger intensity of heat, as well as continuous hammering, followed by rapid cooling. Aluminium requires electrolysis to extract it from its ore, which is a long, complex and expensive process. These metals have got harder to extract from their ores as they have become more reactive – gold, unreactive, is at the bottom of the Reactivity Series whereas aluminium, very reactive, is much nearer to the top.
Also as time went on, more and more reactive metals could be extracted form their ores because modern people were able to grasp the complex methods. For example, gold was found native first, which was a very simple method as it was found in a stream. This is a very unreactive metal. Later on, copper could be extracted from its ore using heat and oxygen, which is a slightly more difficult method. Copper is more reactive than gold and higher in the Reactivity Series, although it is not very reactive. Further on in time, iron and steel were extracted from iron ore using intense, high temperatures of heat fuelled by carbon, continuous hammering and rapid cool, which is a much more difficult and complex method than that of copper and gold. Iron is much more reactive than both copper and gold and higher in the Reactivity Series. After a while aluminium was extracted from its ore through electrolysis, a large, expensive and far more difficult method than all the other metals mentioned (gold, copper, iron). Aluminium is also much higher in the Reactivity Series and much more reactive. This proves that metals higher in the Reactivity Series, which are more reactive, have more complex methods of extraction not only because they are more reactive but also because they took much longer to find ways to extract them from their ores, as proven from the past methods.
Therefore I can predict that in future, as time continues we will be able to extract much more reactive metals from their ores, through more complex methods. I can predict this after reviewing past activities shown in this essay, where as time continued more reactive metals were able to be extracted from their ores through more complex methods. However this is just a prediction, I do not know whether it will happen, as that will require further research into experimentation with metals and methods of extraction from their ores. That is another essay entirely!
