Now, molar mass is a physical property that represents the mass of a substance divided by the amount of that substance. We're going to say the SI unit for mass is kilograms, and the SI unit for the amount of a substance is moles. But molar mass is generally shown as being in units of grams per mole.
And remember, when we see our shaded purple boxes, that means that's a definition or some type of formula you need to memorize. In this case, you need to memorize the molar mass formula. Molar mass itself equals grams per mole.
And what you also need to realize is that molar mass is just one term that can talk about this relationship of grams per mole. Besides molar mass, you might also hear or refer to as molar weight, molecular weight, or molecular mass. So just remember, all of these are talking about the same thing. They're all referring to the relationship of grams per mole being mass of a substance divided by the amount of that substance.