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.
Sodium has a positive 1 charge and chloride has a negative 1 charge. Thus one sodium cation cancels one chloride anion resulting in the formula Na1Cl1 or NaCl. This formula is called the formula unit since it represents only one unit of the vast NaCl array or lattice. Below are other examples of simple ionic compounds made up of single atom (monatomic) ions: Polyatomic ions and compounds: The ionic compounds above were made up of monatomic ions.