Saturday 12 September 2015


Extraction of Metals


Chemistry tuition classes in Miracle Learning Centre is very useful. If you do not understand chemistry, you must definitely attend the chemistry tuition class at Miracle Learning Centre. Let us learn about extraction of metals in this chemistry tuition lesson.

Your chemistry tuition teacher at Miracle Learning Centre will teach you about extraction of metals. Very reactive metals like potassium, sodium, calcium, aluminium and magnesium, are extracted by electrolysis. For example, to obtain sodium, we need to electrolyse molten sodium chloride. To obtain aluminium, we electrolyse bauxite, molten aluminium oxide. Cryolite is added to lower the melting point of aluminium oxide. Hence, less energy is needed to maintain aluminium oxide in the molten state. Cryolite is also used because cryolite is soluble in aluminium oxide.

The moderately reactive metals like zinc and iron are extracted by reduction by carbon. Extraction of iron is carried out in the blast furnace. The raw materials are haematite, coke and limestone. Iron(III) oxide(haematite) is reduced by carbon monoxide to form iron and carbon dioxide.

The student at Miracle Learning Centre asked, "How is the impurities in the blast furnace removed?" The chemistry tuition teacher at Miracle Learning Centre replied, "Calcium carbonate breaks down to become calcium oxide and carbon dioxide. Calcium oxide reacts with the acidic impurities, silicon dioxide, to form slag. Slag is also known as calcium silicate."

Miracle Learning Centre hope you have understood the extraction of metals and how it helps you to answer chemistry tuition questions. Do come to Miracle Learning Centre for more chemistry tuition lessons to learn more about extraction of metals and chemistry.

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