Which element in period 2 of the periodic table has an atomic mass closest to 11?

• A. Nitrogen (N)
• B. Boron (B)
• C. Lithium (Li)
• D. Carbon (C)

Answer: (B)

Verified step by step guidance

1. Identify the elements in period 2 of the periodic table. Period 2 includes Lithium (Li), Beryllium (Be), Boron (B), Carbon (C), Nitrogen (N), Oxygen (O), Fluorine (F), and Neon (Ne).
2. Recall or look up the atomic masses of the given elements: Lithium (Li), Boron (B), Carbon (C), and Nitrogen (N). Atomic mass is usually given in atomic mass units (amu).
3. Compare each atomic mass to the target value of 11 amu by calculating the absolute difference: \(|\text{atomic mass} - 11|\) for each element.
4. Determine which element has the smallest difference from 11 amu, meaning its atomic mass is closest to 11.
5. Select that element as the answer, understanding that atomic mass reflects the weighted average of isotopes and is a key property of each element.