need the answer

Question

The average atomic mass of nitrogen is 14.0067 amu. Predict which isotope listed below is the most abundant in nature.

  they are equally abundant

 

  Nitrogen-15

 

  Nitrogen-13

 

  Nitrogen-14

 

Answer 1

The average atomic mass is a WEIGHTED average, meaning the more abundant an element is, the closer the average will be to that number. If nitrogen has an average atomic weight of 14.0067 between three different isotopes, N-13, N-14, and N-15, then the isotope with the mass closest to 14.0067 is the most abundant.

Between 13, 14, and 15, the mass number 14 is closest to 14.0067 amu, therefore, Nitrogen-14 is the most abundant nitrogen isotope.