Which of the following is closest to the atomic mass of oxygen (O) as listed on the periodic table?

• A. 16.00 u
• B. 14.01 u
• C. 1.008 u
• D. 12.01 u

Answer: (A)

Verified step by step guidance

1. Understand that the atomic mass of an element listed on the periodic table represents the weighted average mass of all naturally occurring isotopes of that element, measured in atomic mass units (u).
2. Recall that oxygen (O) has several isotopes, but the most abundant isotope is oxygen-16, which heavily influences the average atomic mass.
3. Recognize that the atomic mass of oxygen on the periodic table is close to 16.00 u because it reflects this weighted average, not just a single isotope mass.
4. Compare the given options: 14.01 u (close to nitrogen's atomic mass), 1.008 u (hydrogen's atomic mass), 12.01 u (carbon's atomic mass), and 16.00 u (oxygen's atomic mass).
5. Conclude that the value closest to oxygen's atomic mass is 16.00 u, as it matches the standard atomic weight listed on the periodic table.