Question

nitrogen is made up of two isotopes N-14 and N-15 given nitrogen's atomic weight of 14.007u, what is the percent abundance of each isotope? plzzzzzzzzzzzzzzzzzzz answer this its urgent plzzz answer this

Answer 1

14.007= 14 X x  +  15X( 100-x)
             _________________  ;
                       100
1400.7=14x+1500-15x;
x = 1500-1400.7
x= 99.3
100-x=0.7;

Answer 2

The percentage of  N-14 is 99.3% and the percentage of N-15 is 0.7%

- let the percentage of  N-14 = x

- Then, percentage of N-15 = (100-x)

- The atomic weight of nitrogen is given as 14.007 u.

⇒14.007 = {14 × x + 15 × (100-x)}/100

  14.007 = (14x + 1500 - 15x)/100

  1400.7 = 1500 - x

           x = 1500-1400.7

           x = 99.3 %

- Thus the percentage of  N-14 = x = 99.3%

- Then, percentage of N-15 = (100-x) = (100 - 99.3) = 0.7%