The mass of atoms can vary depending on the specific element. However, atoms are incredibly small, and their masses are typically expressed in atomic mass units (amu) or daltons (Da).
One atomic mass unit (amu) is defined as one-twelfth the mass of a carbon-12 atom, which is approximately 1.66 x 10^(-24) grams. Here are the approximate atomic masses of a few common elements:
- Hydrogen (H): 1.00784 amu
- Carbon (C): 12.0107 amu
- Nitrogen (N): 14.0067 amu
- Oxygen (O): 15.9994 amu
- Sodium (Na): 22.9898 amu
- Iron (Fe): 55.845 amu
- Gold (Au): 196.9665 amu
These values represent the average atomic masses of the naturally occurring isotopes of each element. Isotopes are variants of an element with different numbers of neutrons, which can slightly affect the atomic mass. The atomic masses listed are the weighted averages, taking into account the relative abundances of different isotopes.
It's worth noting that when atoms combine to form molecules, the mass of the resulting molecule is equal to the sum of the masses of its constituent atoms.