If the open-angle glaucoma is not specified as primary, assign code 365.10. The residual stage of open-angle glaucoma is classified to code 365.15. Assign code 365.01 for open-angle glaucoma with borderline intraocular pressure.
Return to Mole Menu. Percent composition is the percent by mass of each element present in a compound. Water, H2O, is the first example. One mole of water is 18.0152 grams. In that compound, there are two moles of H atoms and 2 x 1.008 = 2.016 grams. That's how many grams of hydrogen are present in one mole of water.
Mass of reactants = mass of products. Law of Constant Composition. 1  The percentage composition by mass in particular compounds never varies. 2  In other words, in the formation of a compound, the mass of 1 element needed to combine with a given mass of another is always the same. 3  E.g. 39.37% Na: 60.73% Cl for compound NaCl.