Which of the following is closest to the atomic mass of barium (Ba)?

• A. 88.91 u
• B. 137.33 u
• C. 183.84 u
• D. 55.85 u

Answer: (B)

Verified step by step guidance

1. Understand that the atomic mass of an element is the weighted average mass of all its naturally occurring isotopes, measured in atomic mass units (u).
2. Recall that barium (Ba) is an element found on the periodic table with an atomic number of 56, which helps identify its position and typical atomic mass.
3. Look up the atomic mass of barium on a reliable periodic table or reference source, which lists the average atomic mass based on isotopic distribution.
4. Compare the given options (88.91 u, 137.33 u, 183.84 u, 55.85 u) to the known atomic mass of barium from the reference.
5. Select the value closest to the known atomic mass of barium, which is approximately 137.33 u.