A sample of phosphorus was isolated and analyzed to determine the percent abundance of each isotope. The results are recorded in the table. Isotope

Mass (amu)

Percent Abundance

Phosphorus-29

29

5%

Phosphorus-31

31

71%

Phosphorus-32

32

24%

Based on the data, which statement gives the best reasoning to support that the average atomic mass for the sample of phosphorus based on its isotopes is 31.14 amu?

A.
Phosphorus-31 makes up the majority of the sample so the average atomic mass should be close to 31.

B.
It is the sum of neutrons and electrons in the isotopes found in a sample.

C.
It is the total number of neutrons, protons, and electrons in the isotopes found in a sample of phosphorus.

D.
It is the mean of all of the different isotopes of phosphorus present in the sample.