For example, you may have a card that says that the atom you are looking for has 5 neutrons. You would look at the periodic table to find an atom that you could add 5 to its number of protons that ...

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.

The atomic mass is usually measured in atomic mass units (amu), where 1 amu is defined as one-twelfth of the mass of a carbon-12 atom. >Mass of Neutron = 1.008 amu >Mass of Proton = 1.00727647 amu ...

Atomic bombs work via nuclear fission. When enough radioactive material undergoes fission, ... When the two cores of uranium hit each other, critical mass was reached, causing an atomic explosion.

The relative atomic mass, A r, of an element is calculated from: the mass numbers close mass number The number of protons and neutrons found in the nucleus of an atom. of its isotopes; ...

For example, a helium atom has an atomic mass of 4, but an atomic number (or positive charge) of 2. Since electrons have almost no mass, it seemed that something besides the protons in the nucleus ...