Final answer:
The average atomic mass of an element is a weighted average of the masses of the isotopes of that element. The gizmo calculates the average atomic mass by taking into account the relative abundance and the masses of the different isotopes. The impact of isotopic abundance on atomic mass is significant and the average atomic mass is important in chemistry for stoichiometry calculations.
Step-by-step explanation:
In chemistry, the average atomic mass of an element is a weighted average of the masses of the isotopes of that element. Isotopes are variants of an element that have different numbers of neutrons in their atomic nucleus but the same number of protons. The gizmo calculates the average atomic mass by taking into account the relative abundance (the fraction of an element that is a given isotope) and the masses of the different isotopes. The impact of isotopic abundance on atomic mass is significant because it determines the relative contribution of each isotope to the average atomic mass. In chemistry, the average atomic mass is important because it is used to calculate stoichiometry and determine the amount of a substance in a chemical reaction.