Ions, Electrolytes, Metals and Ionic Bonding in Fluid

Ions, Electrolytes, Metals and Ionic Bonding

Learning objectives:


• To understand the general principles of ions and ionic bonding.
•To understand some important functions of both anions and cations in the body.
•To appreciate the diverse uses of elements and ions in various metabolic Processes of the body.

The movement of sodium and potassium ions back and forth through the cell membranes gives rise to electrical impulses and nerve transmissions within the body. This can become disrupted with increasing dehydration. Any water-soluble material, including foods and body fluids, contains positively and negatively charged ions. Many of the cell processes are controlled by adjusting the concentration of these ions entering or leaving the cells of our body. Get these concentrations out of balance, and messages around the body go haywire; thinking is affected and cell stability is disturbed.

1. Introduction to ionic bonding:
You will already realize from earlier knowledge that, for an atom to gain stability when it forms a compound, it tries to gain or lose electrons to make its outer electronic structure that of an ‘inert gas’. Some atoms in molecules achieve this by ‘sharing’ electrons, as in the case of covalent bonding. There is another way of achieving outer electron stability. This is by complete donation, to another atom, or complete acceptance of electrons from another atom. In so doing positive or negative ions are created. These two oppositely charged ions attract each other, tightly holding onto each other. The bonding holding these charged particles together is called ‘ionic bonding’. A typical example of a material containing ions is sodium chloride, NaCl.
• Sodium, Na, atoms have an electronic structure of 2.8.1;
• Chlorine, Cl, atoms have an electronic structure of 2.8.7.