Bonding, Structure and Properties

When atoms join together, either with the same atom or a different atom, the way it joins, has considerable effect on its structure and then consequently on its properties. The joining of an atom to another atom is called Bonding. Bonding involves each atom either donating or accepting electron from another atom. It is also done through sharing electrons. There are three types of bonding that will be discussed here.

 Ionic Bonding

 The bonding involves ions as the name suggests. When an atom becomes a positive ion by losing an electron, this positive ion will look for a negative ion to attract. A negative ion will be the atom that has gained an electron. When these positive and negative ions meet, through attraction of opposites a bonding will be formed, which is known as ionic bonding.

 The substances that would have this type of bondings are compounds of metals with non-metals. For example Sodium Chloride, which involves metal such as Sodium and non-metal such as Chlorine, both become ions. Sodium has one electron in its outer shell, which it will lose to become a positive ion. Chlorine has seven electrons in its outer shell therefore will gain one electron to form a stable outer shell and become a negative ion. The structure, which is present in ionic bonded compounds, is Giant Lattice.  Ionic bonding shows properties of high melting and boiling point. They are very hard but brittle and conduct electricity when dissolved in water, or molten. They are often soluble in water and generally insoluble in non-polar solvents.

Covalent Bonding

 This type of bonding involves sharing of electrons between the two atoms. It is present in non-metals such as Carbon, Chlorine, and Oxygen. For example, in Oxygen, there are 6 electrons in the outer shell. It would bond with another Oxygen by sharing its two electron with other Oxygen’s two electron therefore sharing a total of four electrons.

 This is a double bond. In a single bond only one pair of electrons are shared such as between Chlorine and Chlorine.

 Covalent bonds are strong and have a very high melting and boiling point. It does not conduct electricity and is insoluble in water and non-polar solvents.

Metallic Bonding

 This bonding joins metal atoms together for example Magnesium atoms. Many Mg Atoms bond together to form a solid metal.

 Magnesium atoms are positive ions surrounded by delocalised electrons. Due to these delocalised electrons, they conduct electricity. The melting and boiling points are generally high in Metallic bonding.