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Answer: The average atomic mass of nitrogen is 14.0066 amu
Explanation:
Mass of isotope N-14 = 14.00307 amu
% abundance of isotope N-14= 99.64% = [tex]\frac{99.64}{100}[/tex]
Mass of isotope N-13 = 15.0001 amu
% abundance of isotope N-13= (0.36)% = [tex]\frac{0.36}{100}[/tex]
Formula used for average atomic mass of an element :
[tex]\text{ Average atomic mass of an element}=\sum(\text{atomic mass of an isotopes}\times {{\text { fractional abundance}})[/tex]
[tex]A=\sum[(14.00307)\times \frac{99.64}{100})+(15.0001)\times \frac{0.36}{100}]][/tex]
[tex]A=14.0066amu[/tex]
Therefore, the average atomic mass of nitrogen is 14.0066 amu