If I mix 3.0 mol of N2(g), 2.0 mol of Cl2(g), 4.0 mol of O2(g) and 1.0 mol of H2(g), what is the mole fraction of O2(g)? If the total pressure is 2.00 atm, what is the partial pressure of O2(g)?

Ican determine the molar mass of an element by looking on the under the atomic mass for the element. for example the molar mass of phosphorus is 30.974 grams/mole. avogadro’s number tells me the amount of representative particles in 1 mole of any substance. this means 12.011 gram sample of carbon and a 32.0 gram sample of sulfur have the same number of atoms.