Atoms per Mass

Calculates the number of atoms in a certain mass of a chemical element. Enter mass, unit and element or atomic mass. The number is put out in scientific notation (ten to the power of), as numeral and in mole. One mole are 6.02214076 * 10²³ particles, this is the Avogadro constant. At this amount of particles, the carbon isotope C 12 has the mass of 12 grams. Please specify the mass and select the atom or enter the atomic mass.

Example: one troy ounce of gold (element 79), which are 31.1034768 grams, contains about 9.5097 * 10²² or 95.1 sextillion gold atoms, a bit more than one seventh mole.

The calculation works as follows: the mass in grams is divided by the atomic mass (in the case of gold from the example above, this is 196.966552) and multiplied by Avogadro's constant. Instead of an atomic mass, a molecular mass can just as easily be used, in which case the number of molecules is output as particles. If the input was an atomic mass, the particles are the corresponding atoms.

The mass of each chemical element is their average atomic mass, taking into account the distribution of the isotopes of each element found on Earth. The individual preset values ​​can be found in the atomic mass calculator. If you assume a different isotopic distribution, you must enter the atomic mass directly. A given mass of an element tends to contain more particles the lower the atomic number of the element, and the higher the atomic number, the more particles it contains. This is because the atomic number is the number of protons in the atomic nucleus. Neutrons are still found there in varying numbers, usually more than protons. The more protons there are, the more neutrons the atomic nucleus needs to be stable.