The atomic mass of an element is
A)the mass of the most abundant isotope of that element.
B)the weighted average of the masses of the naturally occurring isotopes of that element.
C)the arithmetic average of the masses of the isotopes of that element.
D)the ratio of the mass of one atom of an isotope of that element to the mass of hydrogen.

Question

Quizplus · Accepted Answer

The atomic mass of an element is calculated as the weighted average of the masses of all the naturally occurring isotopes of that element. This means that the atomic mass takes into account the abundance (percentage occurrence) of each isotope in nature. Therefore, option B is the correct answer. Option A is incorrect because it only considers the most abundant isotope and ignores the contribution of other isotopes. Option C is also incorrect because it assumes that all isotopes contribute equally to the atomic mass. Option D is incorrect because the atomic mass scale is based on carbon-12 as the standard, not hydrogen.

The Atomic Mass of an Element Is