What is the Difference Between Atomic Mass and Molar Mass?

The main difference between atomic mass and molar mass lies in the unit of measurement and the quantity they represent. Here are the key differences:

• Atomic Mass:
• Represents the mass of a single atom or molecule of a substance.
• Expressed in atomic mass units (amu), which is defined as $\frac{1}{12}$ of the mass of a single carbon-12 atom.
• For example, the atomic mass of hydrogen is approximately 1 amu, while that of sodium is about 23 amu.
• Molar Mass:
• Represents the mass of one mole of a substance.
• Expressed in grams (g).
• The molar mass of a substance is numerically equivalent to the atomic mass of the substance in amu. For example, one mole of hydrogen has a mass of approximately 1 g, while one mole of sodium has a mass of about 23 g.

In summary, atomic mass refers to the mass of a single atom or molecule, while molar mass refers to the mass of one mole of a substance. Atomic mass is expressed in atomic mass units, while molar mass is expressed in grams.

Comparative Table: Atomic Mass vs Molar Mass

Here is a table that highlights the differences between atomic mass and molar mass:

To illustrate the difference, consider the compound sodium chloride (NaCl). The atomic mass of sodium is 22.99 a.m.u., and the atomic mass of chlorine is 35.45 a.m.u.. The molar mass of sodium is 22.99 g/mol, and the molar mass of chlorine is 35.45 g/mol. While atomic mass is specific to individual atoms, molar mass is related to the mass of one mole of a substance, making it more relevant for chemical reactions and calculations involving macromolecules.