Question

Topic the structure of chemical substance

Choose any article or journal related to the structure of chemical substance.that will support your answer. Cite your references and use APA for your Bibliography. Write at least 1,500 words.

Answer 1

CHEMICAL STRUCTURES

Atoms can be divided into 2 categories, metal and non metals. They together are combined to form different chemical substances. The atoms in these chemical substances are bonded through different type of chemical bonds such as ionic bond ,covalent bond and metallic bond.

Ionic bonding

The substances which have ionic bonding are arranged in 3D geometric pattterns which go on forever. We call this as a giant ionic structure. All ionic compunds have giant ionic structures. The ions are held together by ionic bonds (Electrostatic attraction between the oppositely chrged ions.) These bonds are strong, requiring a lot of energy to break. The electrostatic attraction of each ion affects all other ions around it. It acts equally in all directions. The ionic compounds genrally have a very high melting and boiling points , it is because of the high amount of heat energy required to break the very strong ionic bonds between oppositely charged ions. Ionic compounds are generally easily soluble in ionic solvents but insoluble in organic solvents this is because ions in ionic solvents attract oppsitely charged ion of the compond and help in breaking the ionic bond between the compound.Solid ionic compunds do not conduct electricity as there are no carge carriers free to move but once they are melted then they conduct electricity because ions are free to move carrying the electric charge .

COVALENT BONDING

Substances with covalent bonding are often made of individual molecules. These are simple molecules covalent bond is form genrally between non metal to non metal.These molecules do not conduct electricity, either whwn solid or liquid , because there are no crge carriers to carry electrical charge.Melting point and boiling points are low because the intermolecular forces between the individual molecules are weak. Overcoming these forces does not take much energy, as no bonds need to be broken.

METTALIC STRUCTURES

The arrangement of layers of metal ions, surrounded by delocalised electrons is called a giant metallic structure. Many of the properties of metals are due to there bonding and structure.Because the metallic bonds throughout the lattice are very strong it takes a lot of energy to break the lattice apart so that the metal ions are free to move. This is why metals have high melting and boiling points. The higher the charge on metals ion , the stronger the metallic bonds will be , and so the higher the melting point. For e.g. Magnesium has higher melting point than sodium. The delocalised electrons in a metal can move throughout the lattice. These are charge carriers , so metals conduct electricity wheather solid or molten. Metals are also good conductors of heat because the delocalised electrons can spread the vibrational energy through the metal lattice. Metals are ductile and malleable in nature as the layers in a pure metals can be hammered and bent into different shapes or drawn out in wires.

ALLOYS

An alloy is a metal which has been mixed with small amount of other metals to give it special properties. For e.g. steel is an alloy of iron with other metals which stops the iron rusting and makes it harder for use in tools , amalgam is alloy of mercury with silver or tin which is used for dental fillings because it can be shaped when warm and resists corrosion ,gold is also an alloy as pure gold is too soft to be used , so it is mixed with copper, silver etc .