If we compare a mole of carbon atoms to a mole of oxygen atoms, which of the following statements is true?

• A. A mole of oxygen atoms contains more atoms than a mole of carbon atoms.
• B. A mole of carbon atoms contains more atoms than a mole of oxygen atoms.
• C. A mole of carbon atoms has a greater mass than a mole of oxygen atoms.
• D. Both contain the same number of atoms.

Answer: (D)

Verified step by step guidance

1. Recall the definition of a mole: one mole of any substance contains Avogadro's number of particles, which is approximately \$6.022 \times 10^{23}$ entities.
2. Understand that this means one mole of carbon atoms and one mole of oxygen atoms each contain exactly the same number of atoms, regardless of the element.
3. Recognize that the difference between the two lies in their masses, not the number of atoms, because carbon and oxygen have different atomic masses.
4. Note that the atomic mass of carbon is approximately 12 g/mol, while the atomic mass of oxygen is approximately 16 g/mol, so a mole of oxygen atoms has a greater mass than a mole of carbon atoms.
5. Conclude that the correct statement is that both a mole of carbon atoms and a mole of oxygen atoms contain the same number of atoms.