An element has the same type of atoms. In some elements, these atoms exist on their own in free state, and in others, they can exist in combination with other atoms. These combinations are known as molecules of the element, e. g. two atoms of oxygen combines to form a molecule. Every atom has a specific mass known as atomic mass.

Match the names of the elements with the corresponding symbols. Carbon Cl Sulphur Mn Chlorine Na Magnesium C Zinc Mg Manganese S Sodium K Gold Fe Iron Zn Potassium Au

The first alphabet of the English name of an element is used as a symbol. e.g. 'O' stands for oxygen. If the name of more than two compounds start with the same alphabet, then another alphabet should be added to the first one. In this situation, the first alphabet should be in capital letters and the second one in small letters. For some alphabets, the symbol is derived from their Latin name. Carbon C Sulphur S Chlorine Cl Magnesium Mg Zinc Zn Manganese Mn Sodium Na Gold Au Iron Fe Potassium K

Match the names of elements with their atomicity.- Iodine 8 Sulphur 4 Phosphorous 1 Sodium 2

Element name Atomicity Iodine 2 Sulphur 8 Phosphorous 4 Sodium 1 The number of atoms, present in a molecule of an element is known as atomicity. We can write formulas of elements by knowing the number of atoms in a molecule. For example atomicity of ozone is three.