Fluorine are present in water and plants. In human body fluorine in is also present in bones, teeth and blood. Atomic number of fluorine is 9 and atomic weight is 18.998. The atomic radius is 72 and ionic radius will be 136.

Fluorine will be melted out at a temperature of -223 degree centigrade and its boiling point is -118 degree centigrade. The density of fluorine is 1.11 and the energy of dissociation is 37.80. Fluorine having a electron affinity which is 3.70 and their oxidation potential is 2.87 .

Fluorine is both prepared in laboratory as well as on industrial scale. In industries fluorine can be prepared by the electrolysis of potassium hydroxide as a result the fluorine will be obtained but it is not pure in nature. So the purification process will be used to obtained pure fluorine.

Fluorine react with hydrogen at a very low temperature -250 to degree centigrade to farm hydrogen fluoride. When it react with sodium to farm sodium fluoride.

Chlorine reacts with water to produce hydrogen gas. When it reacts with halogen like chlorine, bromine, iodine to farm inter-halogen. Fluorine is used in the preparation of different compounds in the laboratory and also the preparation of chemicals.

In industries, it also used in the manufacturing of different products like toothpaste and fluorine used in this product is in the form of fluorides.