Which of the following statements about the mole concept is NOT correct?

• A. One mole of carbon dioxide (CO_2) contains one mole of carbon atoms and two moles of oxygen atoms.
• B. One mole of any substance contains 6.022 × 10^{23} particles.
• C. The molar mass of a compound is the mass of one mole of that compound.
• D. One mole of oxygen gas (O_2) contains 6.022 × 10^{23} oxygen atoms.

Answer: (D)

Verified step by step guidance

1. Step 1: Understand the mole concept, which states that one mole of any substance contains exactly \$6.022 \times 10^{23}$ particles (Avogadro's number). These particles can be atoms, molecules, ions, or formula units depending on the substance.
2. Step 2: Analyze the first statement: One mole of carbon dioxide (CO\(_2\)) contains one mole of carbon atoms and two moles of oxygen atoms. Since CO\(_2\) has one carbon atom and two oxygen atoms per molecule, this statement is correct.
3. Step 3: Analyze the second statement: One mole of any substance contains \$6.022 \times 10^{23}$ particles. This is the definition of a mole and is correct.
4. Step 4: Analyze the third statement: The molar mass of a compound is the mass of one mole of that compound. This is a fundamental definition in chemistry and is correct.
5. Step 5: Analyze the fourth statement: One mole of oxygen gas (O\(_2\)) contains \$6.022 \times 10^{23}\( oxygen atoms. Since O\)_2\( is a diatomic molecule, one mole of O\)_2\( molecules contains \)6.022 \times 10^{23}\( molecules, but each molecule has 2 oxygen atoms, so one mole of O\)_2\( molecules actually contains \)2 \times 6.022 \times 10^{23}$ oxygen atoms. Therefore, this statement is NOT correct.