The atomic mass of elements is measured with the help of unified atomic mass units. One unified atomic mass unit can be quantified as the weight of one-twelfth of the mass of a carbon-12 atom considering that it is at rest. Since protons and neutrons account for almost all of the mass of the given atom, the atomic mass of a given element is almost equal to its mass number.
What is the Atomic Mass of Elements?
The atomic mass of an element can be described as
the total mass of one atom of the given element. Its unit is called the unified atomic mass unit and is denoted by the symbol ‘u’.
Standard atomic weight is used to give the value of the mean of the atomic masses in a mixture of isotopes in a given sample of an element.
| Learn more ⇒ Interactive Periodic Table |
Atomic Mass of First 30 Elements
Given below is a table that lists the first 30 elements based on atomic number and their corresponding atomic mass.
| ATOMIC NUMBER | ELEMENT | ATOMIC MASS |
| 1 | Hydrogen | 1.008 |
| 2 | Helium | 4.0026 |
| 3 | Lithium | 6.94 |
| 4 | Beryllium | 9.0122 |
| 5 | Boron | 10.81 |
| 6 | Carbon | 12.011 |
| 7 | Nitrogen | 14.007 |
| 8 | Oxygen | 15.999 |
| 9 | Fluorine | 18.998 |
| 10 | Neon | 20.180 |
| 11 | Sodium | 22.990 |
| 12 | Magnesium | 24.305 |
| 13 | Aluminium | 26.982 |
| 14 | Silicon | 28.085 |
| 15 | Phosphorus | 30.974 |
| 16 | Sulfur | 32.06 |
| 17 | Chlorine | 35.45 |
| 18 | Argon | 39.948 |
| 19 | Potassium | 39.098 |
| 20 | Calcium | 40.078 |
| 21 | Scandium | 44.956 |
| 22 | Titanium | 47.867 |
| 23 | Vanadium | 50.942 |
| 24 | Chromium | 51.996 |
| 25 | Manganese | 54.938 |
| 26 | Iron | 55.845 |
| 27 | Cobalt | 58.933 |
| 28 | Nickel | 58.693 |
| 29 | Copper | 63.546 |
| 30 | Zinc | 65.38 |
The Molecular mass of an element can be calculated by adding the atomic masses of each of its constituents. There are many ways to find the atomic mass of an element, but the easiest way is to look it up on the periodic table of elements.