Answer:
The mass of Carbon-12 is exactly 12 amu. But, that is not the number that is reported in your periodic table. Carbon as it exists in nature is not all carbon-12. There is some small amount of carbon-13 and even traces of carbon-14 in there. The periodic table reports the average mass of the carbon as it is found in nature, not that of pure carbon-12. The average mass of carbon is slightly heaver than carbon-12, because of the slight amounts of those heaver isotopes of carbon in nature.
Mark me as brainliest please
Explanation:
