general chemistry
posted by Alaa on .
naturally occuring chlorine is composed of 35CL with atomic mass of 34.969 37CL with atomic mass of 36.966 the average atomic mass id 35.453
what are the percantages of each isotope in naturally occuring chlorine ?

Let the fraction of Cl35 be x and that of Cl37 y.
(x)(34.969)+(y)(36.966)=35.453
Since the total of x and y must equal one, substitute y=1x.
Solve for x. Solve for y. Multiply each one by 100 to convert to percent.