Silicon, which makes up approximately 25% of the Earth's crust by mass, is used widely in the modern electronics industry. It has three naturally occurring isotopes, 28Si, 29Si, and 30Si. Calculate the atomic mass of silicon.
Isotope Isotopic Mass (amu) Abundance %
28Si 27.976927 92.23
29Si 28.976495 4.67
30Si 29.973770 3.10
A) 29.2252 amu
B) 28.9757 amu
C) 28.7260 amu
D) 28.0855 amu
E) 27.9801 amu
Answer: D
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