As in other autoimmune diseases such as lupus and rheumatoid arthritis, the bodyâs natural ability to attack invading viruses and bacteria goes haywire and mistakenly sees healthy body proteins as enemies. Redness, pain, heat and swelling signal that the immune system is on the warpath.
Formal Charge = [# valence electrons on neutral atom] â [(# lone electron pairs) + (Â½ # bonding electrons)] 1  Valence electrons = corresponds to the group number of the periodic table (for representative elements).  Lone Pairs = lone electrons sitting on the atom. Each electron counts as one and so a pair counts as two.
Determine the expected charge of the non-metal using the a similar procedure. Elements in column 17 (F, Cl, Br, I) have a -1 charge in ionic compounds, elements in column 16 (O, S, Se, Te) have a -2 charge, and elements in column 15 (N, P, As, Sb) often have a -3 charge in ionic compounds.The total positive charge of the metal must equal the total negative charge of the non-metal.lements in column 17 (F, Cl, Br, I) have a -1 charge in ionic compounds, elements in column 16 (O, S, Se, Te) have a -2 charge, and elements in column 15 (N, P, As, Sb) often have a -3 charge in ionic compounds.