Atomic mass is the average mass of an atom of an element, taking into account the different isotopes of that element and their relative abundance. It is measured in atomic mass units (amu) and is typically listed on the periodic table under each element's symbol.
Atomic mass is calculated by taking the sum of the mass of each isotope of an element, multiplied by its relative abundance, and then dividing by the total number of isotopes. This gives the average mass of an atom of that element.
Atomic mass is often a decimal number because it is an average that takes into account the different masses of an element's isotopes. These isotopes have slightly different masses due to differences in the number of neutrons in their nuclei, which can affect the overall atomic mass.
No, atomic mass and atomic weight are not the same. Atomic mass is the average mass of an atom of an element, while atomic weight takes into account the abundance of each isotope of that element in nature. Atomic weight is also measured in atomic mass units (amu), but it can be a decimal or a whole number.
Atomic mass is related to the number of protons and neutrons in an atom because it is the sum of these particles that make up an atom's mass. Protons and neutrons have a mass of approximately 1 amu each, while electrons have a much smaller mass and are not included in calculating atomic mass.