Atomic Number and Atomic Mass: Get here the easy notes on atomic number and atomic mass for all the first 30 elements. Know how to calculate atomic mass using atomic number.

Well, each element has its distinct properties owing to its atomic number, atomic mass, ... In the first 20 elements, the three noble gases are Helium (He), Neon (Ne), and Argon (Ar).

Note that you can work out the number of neutrons by subtracting the atomic number from the mass number. In this example, it is 35 – 17 = 18 neutrons. Next page. Isotopes. Previous page.

So, now instead of carbon listed as being 12.0107 atomic mass units with a measurement uncertainty of about 0.0008, it has an official atomic weight of [12.0096; 12.0116], where the brackets and ...

The periodic table of chemical elements, often called the periodic table, organizes all discovered chemical elements in rows (called periods) and columns (called groups) according to increasing atomic ...

Sodium has a mass number of 23amu. Since sodium has 11 protons, the number of neutrons is given by mass number – number of protons (23 - 11) = 12 neutrons. Element ...