## Chemistry 10th Edition

Atomic mass of Iron = $55.8473amu$
Mass of $^{54}Fe = 53.9396 amu$ % abundance = $5.82\%$ Mass of $^{56}Fe = 55.9349amu$ % abundance = $91.66\%$ Mass of $^{57}Fe = 56.9354amu$ % abundance = $2.19\%$ Mass of $^{58}Fe = 57.9333amu$ % abundance = $0.33\%$ Atomic mass of an element is the weighted average of the constituent isotopes. I.e., atomic mass of Iron = $0.0582(53.9396amu)+0.9166(55.9349amu)+0.0219(56.9354amu)+0.0033(57.9333amu)$ Atomic mass of Iron = $55.8473amu$