Here's how it works:
* Isotopes: Isotopes are atoms of the same element that have the same number of protons but a different number of neutrons. This means they have the same atomic number but different atomic masses.
* Natural Abundance: Each isotope of an element exists in nature with a specific percentage known as its natural abundance.
* Average Atomic Mass: The average atomic mass is calculated by taking into account the masses of each isotope and their natural abundances. It's a weighted average, where the weight is the natural abundance.
Formula:
Average Atomic Mass = (Mass of Isotope 1 x Abundance of Isotope 1) + (Mass of Isotope 2 x Abundance of Isotope 2) + ...
Example:
Chlorine has two main isotopes: Chlorine-35 (75.77% abundance) and Chlorine-37 (24.23% abundance).
Average Atomic Mass of Chlorine = (35 amu x 0.7577) + (37 amu x 0.2423) = 35.45 amu
Therefore, the mass of the mixture of isotopes for an element is represented by its average atomic mass, which is found on the periodic table.
