Question

The element chlorine has two naturally occurring isotopes. About 75% of chlorine isotopes are Cl-35 and about 25% are Cl-37.

What is the average atomic mass of chlorine atoms?
A. 35.45 amu
B. 36.45 amu
C. 37.45 amu
D. 38.45 amu

Answer 1

ur answer i would beileve is a

Answer 2

A) 35.45 amu

Step-by-step explanation:

Average molar mass is given as

`M_(avg) = (n_1M_1 + n_2M_2)/(n_1 + n_2)`

here we know that

`n_1 = 0.75`

`M_1 = 35`

`n_2 = 0.25`

`M_2 = 37`

now we have

`M_(avg) = (0.75(35) + 0.25(37))/(0.75 + 0.25)`

`M_(avg) = 35.5`