atomtömeg

Atomtömeg refers to the mass of an atom. It is typically expressed in atomic mass units (amu), where one atomic mass unit is defined as one-twelfth the mass of a carbon-12 atom. This unit is also known as the dalton. The atomtömeg of an element is approximately equal to the sum of the number of protons and neutrons in its nucleus, as electrons contribute very little to the overall mass.

Different isotopes of the same element have the same number of protons but different numbers of neutrons, leading to variations in their atomtömeg. Therefore, the atomic weight listed on the periodic table is usually a weighted average of the masses of all naturally occurring isotopes of that element, taking into account their relative abundance.

The concept of atomtömeg is fundamental in chemistry and physics, enabling calculations related to chemical reactions, molecular masses, and nuclear processes. Precise measurements of atomtömeg are crucial for identifying elements and isotopes and for understanding nuclear binding energies. Advances in mass spectrometry have allowed for increasingly accurate determination of atomic masses.