In chemistry, the atomic mass is the mass of a single atom of any element or compound which can be calculated by summing up the masses of protons and neutrons and is expressed in terms of atomic mass units (or amu). To calculate the atomic mass of a single atom of an element, add up the mass of protons and neutrons. Use this online atomic mass calculator to find the relative atomic weight of any chemical element by just entering its number of protons and number of neutron.
Find the atomic mass of an isotope of carbon that has 7 neutrons and 6 protons?
Atomic Mass = 6 + 7
= 13 .