Medication Summary. Topical antibiotics, systemic antibiotics, or a combination of both is effective therapy for impetigo. Empiric bacterial coverage is aimed at eradicating Staphylococcus aureus and group A beta-hemolytic streptococci (GABHS; also known as Streptococcus pyogenes).
In chemistry, the valence or valency of an element is a measure of its combining power with other atoms when it forms chemical compounds or molecules. The concept of valence was developed in the second half of the 19th century and was successful in explaining the molecular structure of inorganic and organic compounds.
The valency of sodium(Na) is +1 and the valency of oxide(O) is -2. Whenever we make a chemical formula,we keep the positive ion cation first and then we keep the negative ion anion. Na+1 O-2. By criss cross method both the valencies will interchange their places. The final chemical formula will be Na2O.