The mass of one mole of a substance is equal to that substance’s molecular weight. For example, the mean molecular weight of water is 18.015 atomic mass units (amu), so one mole of water weight 18.015 grams. Is mole and molar mass the same? A mole is 6.02⋅1023 (avogadro’s number) molecules of a substance. The molar mass is the amount of Thus, 98 g of H 2 SO 4 = 1 mole of H 2 SO 4. 392 g of H 2 SO 4 = 4 moles of H 2 SO 4. 2) 1 mole of CO 2 = 22.4 litres at STP. i.e. 22.4 litres of CO 2 at STP = 1 mole. 44.8 litres of CO 2 at STP = 2 moles CO 2. 3) 1 mole of O 2 molecules = 6.022 x 10 23 molecules. 6.022 x 10 23 molecules = 1 mole of oxygen molecules. Avogadro’s number is a proportion that relates molar mass on an atomic scale to physical mass on a human scale. Avogadro’s number is defined as the number of elementary particles (molecules, atoms, compounds, etc.) per mole of a substance. It is equal to 6.022 × 10 23 mol -1 and is expressed as the symbol N A. 2. Molar mass is also known by the name molecular weight whereas molecular mass is known to us for determining the mass of a single molecule. 3. Molar mass is expressed in units like in g/mol for higher calculations while molecular mass is expressed in amu i.e. atomic mass unit. 4. The mole provides a link between an easily measured macroscopic property, bulk mass, and an extremely important fundamental property, number of atoms, molecules, and so forth. A mole of substance is that amount in which there are 6.02214076 ×1023 6.02214076 × 10 23. Figure 3.2.4 3.2. 4: Each sample contains 6.022 10 23 atoms —1.00 mol of atoms. formula mass: sum of the average masses for all atoms represented in a chemical formula; for covalent compounds, this is also the molecular mass. molar mass: mass in grams of 1 mole of a substance. mole: amount of substance containing the same number of atoms, molecules, ions, or other entities as the number of atoms in exactly 12 grams of 12 C jflhKzT. Start by converting the molar mass for helium from g/mol to kg/mol. M = (4.00 g/mol) × 1 kg 1000 g M = ( 4.00 g / m o l) × 1 k g 1000 g. M = 4.00 ×10−3 kg/mol M = 4.00 × 10 − 3 k g / m o l. Now, using the equation for urms u r m s substitute in the proper values for each variable and perform the calculation.

is molecular weight and molar mass the same