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Ionic Lattices Iron Pyrite(Iron Sulfide, FeS )
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Presented within the Pyrite bond model, is the ionic bond of Iron and sulfur in the an ionic lattice structures.
The bond occurs as a result of the strong electrostatic attraction between the opposite charges of the positive metallic ion of iron and the negative non-metal ion of sulfur. Within the model the larger blue spheres represent the sulfur while the smaller yellow spheres represent the iron. The structure is a cube because, the atoms form nice square molecules and the molecules join together with other square pyrite molecules.
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As this is a bond occurring between a metal and a non-metal, the metal’s properties allow it to lose electrons to become a cation much easier than gaining electrons to become an anion, this is the opposite to the non-metal sulfur. The bond occurs as a result of a loss of two electrons from the outer shell of the metals for them to become stable, making them cations as they ends up with more protons than electrons; whilst the non-metal atoms gain the electrons to also form a full outer shell, making them anions as it ends up with more electrons than protons. The opposite charges of the two atoms cause the transfer of two electrons from the outer shell of the metal into the outer shell of the non-metal for a noble gas electron configuration, in which they both gain full valence shells. This leads to the attraction
Yellow - Iron between the atoms as they both turn into ions. Therefore their opposite
Purple - Sulfur charges bind them together, thus creating a cubic structure of the ionic bond between the opposite ions. The bond is also known as an electrovalent bond, where the atoms cannot share the electrons due to the metal atom completely losing it’s valence electrons in the outer shell electrons to the outer shell of the non-metal atom to gain full outer shells to be stable like the noble gases. This is due to the concept of electronegativity, which refers to the atom’s need for electrons. The high electronegativity of non-metals; enable them to have control over all the electrons that the metal atom loses control over as a result of it’s low electronegativity.
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In ionic bonding; the solids of the bond are fairly stable compounds due to their strong bond between it’s ion caused by its strong electrostatic attraction between the oppositely charged ions. Ionic solids also have high melting and boiling points, and conduct electricity when melted or dissolved in water, this is also as a result of their strong bond which requires a large amount of energy for them to be broken. However their strong bond also prevents them from conducting electricity in their solid form as the ions are unable to move in this state, but when they are not in their solid form, they are able to move, thus can conduct electricity, this is usually when they have been dissolved in water and the their ions can move freely. This is evident with the mineral pyrite, which is derived from iron and sulfur; iron’s position as a transition metal on the periodic table allows it to be able to lose the electrons of its outer shell to become a positively charged ion; cation. As this results in the and a stable structure within the ionic compound of pyrite; this is the cause of the hardness and brittleness of the substance. This makes it suitable for the uses and applications as an ore of gold as they are assembled under similar conditions and occur together in the same rocks. Pyrite is occasionally used as a gemstone, it is fashioned into beads, cut into cabochons, faceted, and carved into shape, however pyrite is not an excellent jewellery stone because of its hardness, brittleness and the fact that it easily tarnishes.
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Covalent Molecule Ammonia (NH3)
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The covalent molecular bond of nitrogen and hydrogen to form ammonia is represented within this model as for the one nitrogen atom, there are three hydrogen