Let's begin by using the molar mass to find the actual mass of an atom and a molecule. Specifically, we will use the periodic table to find the mass of a single hydrogen atom and the mass of an oxygen molecule (consisting of two oxygen atoms and written O2). Part A Practice Problem: 13. Find the total mass of a molecule of carbon dioxide (CO2). Express your answer in grams per molecule to three significant figures. Submit ? g/molecule Previous Answers Request Answer Incorrect; Try Again Your answer is the molar mass of a molecule. One mole is the amount of a substance that contains as many elementary entities as there are atoms in 0.012 kilograms of carbon-12. Use this information to find the total mass of a molecule. 4 Part B - Practice Problem: What fraction of this total mass is the mass of the carbon atom?