An atom is so small that a single drop of water contains more than a billion atoms. Although tiny, atoms are mostly empty space. The simplified model of the atom is that of a cloud of negative ...

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 ...

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 ...

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 ...

equivalent to the positive charge of the atom) was less than the atomic mass (average mass of the atom). For example, a helium atom has an atomic mass of 4, but an atomic number (or positive ...

Another frontier pursued by cutting edge research here is the crafting of atom-light interactions so precise that a new generation of atomic clocks can be envisioned, whose accuracy approaches 1 ...