Which one of the following has the largest atomic mass?

• A. Iron (Fe)
• B. Uranium (U)
• C. Carbon (C)
• D. Oxygen (O)

Answer: (B)

Verified step by step guidance

1. Identify the atomic masses of each element given: Iron (Fe), Uranium (U), Carbon (C), and Oxygen (O). Atomic mass is typically found on the periodic table and represents the average mass of an atom of that element, measured in atomic mass units (amu).
2. Recall that atomic mass generally increases as you move down a group and across a period in the periodic table, but the most reliable method is to look up the exact atomic masses for each element.
3. List the approximate atomic masses for each element: Carbon (C) is about 12 amu, Oxygen (O) is about 16 amu, Iron (Fe) is about 56 amu, and Uranium (U) is about 238 amu.
4. Compare these values directly to determine which element has the largest atomic mass by identifying the highest numerical value among them.
5. Conclude that the element with the largest atomic mass is the one with the highest atomic mass value from the list, which is Uranium (U).