During the period 1811-1886, the halogens were discovered. They are non-metallic elements such as: Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I) and astatine (At) which are the members of the halogen family. This family constitutes the group 17 of the periodic table. The word halogens have been derived from the Greek word “Halo” that … Read more
Group 15 of the modified long form periodic table consists of five elements: Nitrogen (N), Phosphorus (P), Arsenic (As), Antimony (Sb) and Bismuth (Bi). These elements are collectively called the elements of nitrogen family. Nitrogen and Phosphorus are non-metals, arsenic and antimony are semi-metals or metalloids: bismuth is metallic although not so strong. Some important … Read more
Introduction to Covalent bond In 1916, G.N Lewis suggested that atoms may combine with one another by mutual sharing of their valence electrons. Due to this, the combining atoms attain the nearest noble gas configuration in their valence cells. These shared pairs of electrons are situated exactly or nearly at the midpoint of the combining … Read more