Molar mass of element ------------------------------------ x 100 Molar mass of compound
So, first lets calculate the mass of the compound as a whole. We use the atomic masses on the periodic table to determine this.
Ca: 40.078 g/mol N2 (there is two nitrogens): 28.014 g/mol O6 (there are six nitrogens: 3 times 2): 95.994 g/mol
When we add all of those numbers up together, we get 164.086. That is the molar mass for the whole compound. However, we are trying to figure out what percent of the compound oxygen makes up. From the molar mass, we know that 95.994 of the 164.086 is oxygen. Lets plug those numbers into our equation!
95.994 ----------- 164.086
When we divide those two numbers, we get .585. When we multiply that by 100, we get 58.5.
So, the percent compostition of oxygen in Ca(NO3)2, or, calcium nitrate, is 58.5%.
Include: - Adding cleanser makes the paperclip fall through the water to the base of the dish. - Soap is a surfactant. - Surfactants lessen the surface pressure of a fluid. - The surface strain of water is the thing that upheld the paper cut.