Answer
The atomic mass of chlorine is 35.453 amu.
Work Step by Step
The atomic mass of the element is found by multiplying each isotopic mass by its fraction, and then add all of them.
So to find the atomic mass of chlorine, we have to multiply the isotopic mass of isotope Cl-35 and Cl-37 with their respective fractional abudance:
34.96885 amu x 0.75771 =26.496 amu
36.9659 amu x 0.24229 = 8.956amu
____________________________
Sum: 35.453 amu
So the atomic mass of chlorine is 35.453 amu.
