Assignment: Chemistry Of Magnesium And Silicon

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Assignment: Chemistry of Magnesium and Silicon
Magnesium
Properties
Magnesium is a group is a group 2 element with the symbol, Mg, an atomic number of 12 and has a molar mass of 24.31 [1]. It is made up of 12 protons, 12 neutrons, and 12 electrons. It’s electron configuration is 1s2,2s2,2p6,3s2 this given as noble gas configuration is [Ne]3s2.
It has a melting point of 650 °C and a boiling point of 1090 °C [2]. It has a metallic radius of 150 pm, a coordination number of 72(6), and a density of 1.74 g cm-1 [3]. It is a silvery white metal; this is shared by all of the group 2 elements.
Its bonding with other elements is usually ionic, again shared by all of the group 2 elements.[4] Solid Magnesium however has metallic bonding, in which the metal loses one or more electrons to a common ‘sea’ of electrons. The strength of the bond arises from the
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Occurrence in nature and extraction methods
Magnesium is the 8th most abundant element in the earth’s crust and the 3rd most abundant in seawater. It appears naturally in a number of minerals such as Dolomite (CaCO3∙MgCO3) and as Magnesite (MgCO3) [6].
Magnesium can be extracted from dolomite with the use of ferrosilicon (FeSi) The dolomite is heated, in air, this produces both magnesium oxides and calcium oxides. The mixture of magnesium and calcium oxides is then heated with the ferrosilicon which forms calcium silicate and magnesium [7]
The extraction of magnesium from seawater is a completely different operation which relies on the fact that magnesium hydroxide is less soluble than calcium hydroxide. So to extract the magnesium hydroxide they add CaO to seawater and because its more soluble it displaces the Mg(OH)2 forming a precipitate [6]. The precipitate is then treated with hydrochloric acid.

As an equation it would look like this:
CaO(s) + H2O(l) → Ca2+(aq) + 2OH-(aq)
Mg2+(aq) + 2OH-(aq) →

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