In fact, the periodic table is arranged in order of increasing atomic number. A second number is needed to fully describe an atom. This number is called the mass number. Since the mass of an atom ...

Then, in addition, atomic units usually leave unspecified whether or not a reduced mass is given unit value instead of the electron mass, or indeed whether other modifications have been made (see ...

The Atomic Mass Data Center and its electronic bulletin are tools for the exchange of information on experimental masses, evaluation of masses, extrapolation of masses, and theoretical masses. One of ...

Scientists use the periodic table to quickly refer to information about an element, like atomic mass and chemical symbol. The periodic table’s arrangement also allows scientists to discern trends in ...

This Q-value calculation programme allows you to calculate reaction Q-values and threshold energies and decay Q values based on the 1995 Update to the Atomic Mass Evaluation and to retrieve other ...