Which of the following statements correctly describes molar mass?

• A. Molar mass is the volume occupied by one mole of a gas at standard temperature and pressure.
• B. Molar mass is the mass of one atom of an element, expressed in atomic mass units (amu).
• C. Molar mass is the total number of atoms in one mole of a compound.
• D. Molar mass is the mass of one mole of a substance, expressed in grams per mole (g/mol).

Answer: (D)

Verified step by step guidance

1. Understand that molar mass is a physical property that relates the mass of a substance to the amount of substance in moles.
2. Recall that one mole of any substance contains Avogadro's number of particles, which is \$6.022 \times 10^{23}$ entities.
3. Recognize that molar mass is defined as the mass of one mole of a substance, and it is expressed in grams per mole (\(g/mol\)).
4. Distinguish molar mass from other related concepts: it is not the volume of a gas (which relates to molar volume), nor the mass of a single atom (which is atomic mass in amu), nor the total number of atoms (which is related to Avogadro's number).
5. Therefore, the correct description of molar mass is: it is the mass of one mole of a substance, expressed in grams per mole (\(g/mol\)).