There are two stable isotopes of chlorine: chlorine-35, with a mass of 34.968853 amu; and chlorine-37, with a mass of 36.965903.Given that the average atomic mass of a chlorine atom is 35.45 amu, which of the following statements is true?
A)Chlorine contains almost exclusively of , with very little Cl.
B)Chlorine contains more Cl than Cl.
C)Chlorine contains roughly equal amounts of Cl and Cl.
D)Chlorine contains more Cl than Cl.
E)Chlorine contains almost exclusively of Cl, with very little Cl.

Question

There are two stable isotopes of chlorine: chlorine-35, with a mass of 34.968853 amu; and chlorine-37, with a mass of 36.965903.Given that the average atomic mass of a chlorine atom is 35.45 amu, which of the following statements is true?
A)Chlorine contains almost exclusively of , with very little Cl. 
B)Chlorine contains more Cl than Cl. 
C)Chlorine contains roughly equal amounts of Cl and Cl. 
D)Chlorine contains more Cl than Cl. 
E)Chlorine contains almost exclusively of Cl, with very little Cl.

Quizplus · Accepted Answer

The average atomic mass is closer to Cl-35 than Cl-37, so there must be more Cl-35 atoms present in nature. Therefore, statement B is true: Chlorine contains more Cl-35 than Cl-37.

There Are Two Stable Isotopes of Chlorine: Chlorine-35, with a Mass