The element chlorine has two stable isotopes,chlorine-35 with an atomic mass of 34.97 u and chlorine-37 with an atomic mass of 36.97 u.From the atomic weight found on the periodic table,one can conclude that _____.
A) both isotopes have the same percent natural abundance
B) there is an isotope of nitrogen with an atomic mass of 35.45 u
C) chlorine-35 has the highest percent natural abundance
D) chlorine-37 has the highest percent natural abundance
E) there is an isotope of nitrogen with an atomic mass of 37.95 u

Question

Quizplus · Accepted Answer

The atomic weight found on the periodic table is the weighted average of the atomic masses of all the naturally occurring isotopes of chlorine, taking into account their percent abundance. Since chlorine-35 has a lower atomic mass than chlorine-37, it must have a higher percent natural abundance in order to contribute to the average atomic weight. Therefore, option C is correct. Option A is incorrect because the isotopes do not necessarily have the same percent natural abundance. Option B and E are incorrect as they are not related to chlorine. Option D is incorrect because chlorine-37 would have to be more abundant than chlorine-35 for it to contribute more to the atomic weight, but this is not the case.

The Element Chlorine Has Two Stable Isotopes,chlorine-35 with an Atomic