Examples of molar mass in the following topics:

 Molar mass (M) is equal to the mass of one mole of a particular element or compound; as such, molar masses are expressed in units of grams per mole (g molâ€“1) and are often referred to as molecular weights.
 For a mixture of gases, the molar mass depends on the molar masses of each of its components and on the fractional abundance of each kind of gas in the mixture.
 The average molar mass of a mixture of gases is equal to the sum of the mole fractions of each gas, multiplied by their respective molar masses:
 where m is the mass of the gas, and M is the molar mass.
 Finally, putting the equation in terms of molar mass, we have:

 A substance's molar mass can be used to convert between the mass of the substance and number of moles in that substance.
 The molar mass of any element can be determined by finding the atomic mass of the element on the periodic table.
 For example, if the atomic mass of sulfer (S) is 32.066 amu, then its molar mass is 32.066 g/mol.
 In a compound of NaOH, the molar mass of Na alone is 23 g/mol, the molar mass of O is 16 g/mol, and H is 1 g/mol.
 Since the molar mass of NaOH is 40 g/mol, we can divide the 90 g of NaOH by the molar mass (40 g/mol) to find the moles of NaOH.

 Masstomole conversions can be facilitated by employing the molar mass as a conversion ratio.
 From the relative atomic mass of each element, it is possible to determine each element's molar mass by multiplying the molar mass constant (1 g/mol) by the atomic weight of that particular element.
 The molar mass value can be used as a conversion factor to facilitate masstomole and moletomass conversions.
 The compound's molar mass is necessary when converting from grams to moles.
 After the molar mass is determined, dimensional analysis can be used to convert from grams to moles.

 The molar mass of a particular substance is the mass of one mole of that substance.
 Molar mass is the mass of a given substance divided by the amount of that substance, measured in g/mol.
 The characteristic molar mass of an element is simply the atomic mass in g/mol.
 However, molar mass can also be calculated by multiplying the atomic mass in amu by the molar mass constant (1 g/mol).
 To calculate the molar mass of a compound with multiple atoms, sum all the atomic mass of the constituent atoms.

 Now, recall that density is equal to mass divided by volume:
 This derivation of the Ideal Gas Equation allows us to characterize the relationship between the pressure, density, and temperature of the gas sample independent of the volume the gas occupies; it also allows us to determine the density of a gas sample given its pressure and temperature, or determine the molar mass of a gas sample given its density.
 Instead of using the regular ideal gas equation, PV=nRT, we use a transformed version (D=PM/RT) to solve a problem with density and molar mass.

 If the amount of solute is given in grams, we must first calculate the number of moles of solute using the solute's molar mass, then calculate the molarity using the number of moles and total volume.
 First, we must convert the mass of NaCl in grams into moles.
 We can also calculate the volume required to meet a specific mass in grams given the molarity of the solution.
 This is useful with particular solutes that cannot be easily massed with a balance.
 First we must convert grams of BH3 to moles by dividing the mass by the molecular weight.

 The rate of this movement is a function of temperature, viscosity of the medium, and the size (mass) of the particles.
 Scottish chemist Thomas Graham experimentally determined that the ratio of the rates of effusion for two gases is equal to the square root of inverse ratio of the gases' molar masses.

 , where vrms is the rootmeansquare of the velocity, Mm is the molar mass of the gas in kilograms per mole, R is the molar gas constant, and T is the temperature in Kelvin.

 The equivalent weight of a substance is defined as the molar mass divided by the number of electrons required to oxidize or reduce each unit of the substance.
 What mass of copper will be deposited if a current of 0.22 amp flows through the cell for 1.5 hours?

 Avogadro's number is a proportion that relates molar mass on an atomic scale to physical mass on a human scale.
 Another property of Avogadro's number is that 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.
 This video introduces counting by mass, the mole, and how it relates to atomic mass units (AMU) and Avogadro's number.
 Amedeo Avogadro is credited with the idea that the number of entities (usually atoms or molecules) in a substance is proportional to its physical mass.