What is the formula for calculating moles from mass?

The formula for calculating moles from mass is based on the relationship between the amount of a substance (in moles), its mass (in grams), and its molar mass (in grams per mole). The correct formula states that moles are equal to the mass of the substance divided by its molar mass.

This formula is derived from the definition of molar mass, which is the mass of one mole of a substance. To find out how many moles are present, you take the total mass of the substance you have and divide it by the mass of one mole of that substance (the molar mass). This method allows for the conversion between the mass of a substance and the amount in moles, which is essential in stoichiometry and various calculations in chemistry.

In this context, using mass divided by molar mass provides a straightforward calculation that directly relates the physical quantity of a substance (mass) to the amount of substance in moles, which is a key concept in quantitative chemistry.