[40 points] How do I find the average atomic masses of these?
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Answer:
14.02 amu
Explanation:
The following data were obtained from the question:
Isotope A (N–13):
Mass of A = 13 amu
Abundance (A%) = 28.97%
Isotope B (N–14):
Mass of B = 14 amu
Abundance (B%) = 41.04%
Isotope C (N–15):
Mass of C = 15 amu
Abundance (C%) = 29.97%
Average atomic mass of nitrogen =?
The average atomic mass of nitrogen can be obtained as illustrated below:
Average = [(Mass of A × A%)/100] + [(Mass of B × B%)/100] + [(Mass of C × C%)/100]
= [(13 × 28.97)/100] + [(14 × 41.04)/100] + [(15 × 29.97)/100]
= 3.77 + 5.75 + 4.50
= 14.02 amu
Thus, the average atomic mass of nitrogen is 14.02 amu