Why Aren't All Atomic Masses Whole Numbers?

The video explains that atomic masses are not always whole numbers due to isotopes, which are atoms of the same element with different numbers of neutrons. Using chlorine as an example, the video shows how the relative abundance of isotopes affects the calculation of relative atomic mass. A formula is provided to calculate this weighted mean mass. Another example with bromine is given to reinforce the concept. The video concludes by emphasizing that the relative atomic mass is a weighted mean of isotopes, explaining why these values are not whole numbers.

What are isotopes and how do they relate to atomic mass?

Explain the significance of relative abundance in calculating atomic mass.

How is the relative atomic mass of chlorine calculated based on its isotopes?

What example is given for calculating the relative atomic mass of bromine?

Why are most relative atomic masses not whole numbers?