Question

Why is the atomic mass of iron, 55.845 amu, most similar to the mass of iron-56, yet less than 56 amu? The atomic mass is the simple average of the masses of the two most abundant isotopes. Iron‑56 is the most abundant isotope, so the atomic mass of iron is most similar to the mass of iron‑56. The second most abundant isotope is iron‑54, which reduces the atomic mass to less than 56 amu. The atomic mass is the weighted average of the masses of all of the isotopes. Iron‑56 is the most abundant isotope, so the atomic mass of iron is most similar to the mass of iron‑56. The second most abundant isotope is iron‑54, which reduces the atomic mass to less than 56 amu. The atomic mass is the weighted average of the masses of the two most abundant isotopes. Iron‑56 is the most abundant isotope, so the atomic mass of iron is most similar to the mass of iron‑56. The second most abundant isotope is iron‑54, which reduces the atomic mass to less than 56 amu. The atomic mass is the simple average of the masses of all of the isotopes. Iron‑56 is the most abundant isotope, so the atomic mass of iron is most similar to the mass of iron‑56. The second most abundant isotope is iron‑54, which reduces the atomic mass to less than 56 amu.

Answer 1

Answer:

Iron‑56 is the most abundant isotope, so the atomic mass of iron is most similar to the mass of iron‑56.

Explanation:

The atomic abundance of the isotopes of Iron is:

⁵⁴Fe: 5.82%

⁵⁶Fe: 91.66%

⁵⁷Fe: 2.19%

⁵⁸Fe: 0.33%

Where the Iron-56 is the most abundant isotope of Iron atom

As atomic mass is defined as the sum of the masses of the ions multiplied by its abundance, and the Iron-56 is the most abundance isotope, the atomic mass of Fe most be similar to the ⁵⁶Fe mass because is the most abundant isotope.

Right option is:

Iron‑56 is the most abundant isotope, so the atomic mass of iron is most similar to the mass of iron‑56.