INTRODUCTION Elements are the basic components of all matter. An element is a substance that cannot be broken down into simpler substances through ordinary chemical processes. Many familiar names like copper, silver, gold, oxygen, nitrogen, carbon, and sodium, all are elements. The building block of elements is an atom and each atom has a specific symbol. For example, nitrogen is designated symbol ‘N’, oxygen by symbol ‘O’ and copper by symbol ‘Cu’. Based on the different properties, elements are classified as metals and non-metals. METALS They occur in nature in various forms, so their reactivities also differ greatly. Almost all are found in the earth's crust, while a few are also found in seawater as salts. Aluminium is the most abundant metal on earth. Metals that do not react with oxygen, moisture, carbon dioxide, and other chemicals are found in the free state. Gold, silver, and platinum are found in their native state due to their less reactivity. Metals with high r...