Which unit is commonly used for measuring atomic mass?

• A. atomic mass unit (amu)
• B. liter (L)
• C. mole (mol)
• D. gram (g)

Answer: (A)

Verified step by step guidance

1. Understand that atomic mass refers to the mass of a single atom, which is extremely small and cannot be conveniently measured in grams or liters.
2. Recall that the mole (mol) is a unit used to count particles (atoms, molecules) rather than measure mass directly.
3. Recognize that the liter (L) is a unit of volume, not mass, so it is not appropriate for measuring atomic mass.
4. Learn that the atomic mass unit (amu) is specifically defined to express atomic and molecular masses on a scale relative to the carbon-12 isotope.
5. Conclude that the atomic mass unit (amu) is the standard and commonly used unit for measuring atomic mass.