Which term represents the number of atoms or molecules in one mole (6.022 x 10^23)?

• A. Avogadro's number
• B. mole
• C. molar mass
• D. average atomic mass

Answer: (A)

The key idea is the fixed count of particles that defines a mole. One mole corresponds to 6.022 × 10^23 particles, providing a universal bridge between the microscopic world of atoms and molecules and the macroscopic amounts we can weigh. That count is Avogadro's number, the constant used to convert between number of particles and moles in any substance. So the term represented here is Avogadro's number. In contrast, the mole is the amount of substance, molar mass is the mass per mole, and average atomic mass is the mass of a representative atom on average; none of those specify the exact number of particles per mole.