Which of the following is closest to the atomic mass of lead (Pb)?

• A. 195.1 u
• B. 207.2 u
• C. 238.0 u
• D. 183.8 u

Answer: (B)

Verified step by step guidance

1. Understand that the atomic mass of an element is the weighted average mass of all the naturally occurring isotopes of that element, measured in atomic mass units (u).
2. Recall that the atomic mass listed on the periodic table for lead (Pb) is based on the relative abundances and masses of its isotopes.
3. Identify the given options and compare them to the known atomic mass of lead, which is approximately 207 u.
4. Recognize that 207.2 u is the value closest to the accepted atomic mass of lead, as the other options (195.1 u, 238.0 u, 183.8 u) are significantly different.
5. Conclude that the correct choice is the value closest to the known atomic mass of lead, which is 207.2 u.