Atomic Mass Deficiency

The Atomic Mass Deficiency calculator computes the difference between the components of an atom (protons, neutrons and electrons) and the measure weight of the atom.

INSTRUCTION: Choose units and enter the following:

• (r) Number of Electrons
• (p) Number of Protons
• (n) Number of Neutrons
• (q) Measured mass of the Atom ({{equation,e2b91146-6f34-11e4-a9fb-bc764e2038f2,(Dynamic Periodic Table)}

Mass Deficiency (Δm): The calculator returns the mass deficiency in atomic units, and the binding energy equivalent of that deficiency in mega electron volts (MeV).  However this can be automatically converted to compatible units via the pull-down menu.

The Math / Science

The Atomic Mass Deficiency¹ calculates the difference between the measured mass of an atom and its calculated mass based on protons, neutrons, and electrons. Although electrons are sometimes discounted in the mass deficiency equation because of their very small mass, this equation includes them to ensure precise calculations.   The difference in mass is accounted for by the binding energy in Einstein's famous E=mc² equation.

The Atomic Mass Deficiency equation is:

   Δm = (electrons + protons + neutrons) - actual mass of atom

Where:

• Δm = the difference between the the calculated and measured mass of the atoms
• electrons = the number of electrons in the atom
• protons = the number of protons in the atom
• neutrons = the number of neutrons in the atom
• actual mass of atom = measured mass of atom 

Atomic Mass Calculations and Data

• Mass of an Electron
• Mass of a Proton
• Mass of a Neutron
• Atomic Mass Deficiency
• Atomic Binding Energy
• Charge of a Proton
• Proton Magnetic Moment
• Proton Gyromagnetic Ratio
• Proton Compton Wavelength
• Proton Magnetic Shielding Correction

References

[1] Whitten, et al. "Chemistry" 10th Edition. Pp. 854