One evening last summer, as I strolled along the promenade in Limbe, a small, scenic port town in southwestern Cameroon, I was stopped by a well-dressed young man who greeted me warmly and took me by the hand.
Phosphorus has 3 shells. The outer shell contains 5 electrons. The electronic configuration is :- <br /> 1s2, 2s2, 2p6, 3s2, 3p3.
The group number of an element in the periodic table is the same as the number of electrons in its outer shell. An element in group 1 has 1 electron in its outer shell. An element in group 2 has 2 electrons in its outer shell. An element in group 7 has 7 electrons in its outer shell. An element in group 0 has a full outer shell. The number of electrons in the outer shell gives the element its chemical properties and controls its chemical reactions.