Which has a greater mass: one mole of carbon-12 atoms or one mole of oxygen-16 atoms?

• A. Both have the same mass
• B. It depends on the physical state
• C. One mole of carbon-12 atoms
• D. One mole of oxygen-16 atoms

Answer: (D)

Verified step by step guidance

1. Recall that one mole of any substance contains Avogadro's number of particles, which is approximately \$6.022 \times 10^{23}$ particles.
2. Understand that the molar mass of an element in grams per mole is numerically equal to the atomic mass of the element in atomic mass units (amu).
3. Identify the atomic masses: carbon-12 has an atomic mass of exactly 12 amu, and oxygen-16 has an atomic mass of approximately 16 amu.
4. Since one mole contains the same number of atoms for both elements, compare their molar masses directly: 12 g/mol for carbon-12 and 16 g/mol for oxygen-16.
5. Conclude that one mole of oxygen-16 atoms has a greater mass than one mole of carbon-12 atoms because 16 g is greater than 12 g.