Question

Silicon has three naturally occurring isotopes: Si-28, Si-29, and Si-30. If the average atomic mass of silicon is 28.09, which isotope has the highest isotopic abundance?

A) Si-28
B) Si-29
C) Si-30
D) All of the above have equal isotopic abundance.

Answer 1

The isotope of silicon with the highest isotopic abundance is Si-28, as the average atomic mass of silicon (28.09 amu) is closest to that of Si-28.

Step-by-step explanation:

The question is asking for the isotope of silicon with the highest isotopic abundance, given that the average atomic mass of silicon is 28.09 amu. The isotopes in question are Si-28, Si-29, and Si-30. To determine which isotope has the highest isotopic abundance, we look at the average atomic mass: 28.09 amu is closest to the mass number of Si-28, which is 28. Therefore, it can be inferred that Si-28 has the highest isotopic abundance since the average atomic mass of silicon is heavily influenced by the mass of its most abundant isotope.