Formula: Mass Defect Mass of the nucleus    Neutron number    Proton number   

Formula: Mass Defect
Mass Defect - A Nucleus is Lighter Than the Sum of its Components

Mass difference

The mass difference \(\class{brown}{\delta m}\) of the individual nuclei components and the mass \(\class{brown}{m}\) of the nucleus is not zero. This is called mass defect. This mass difference hides in the binding energy of the nucleus.

Mass of the nucleus

Mass of the nucleus formed by the union of \(N\) neutrons and \(Z\) protons. The nucleus is lighter than the sum of its components (mass defect).

Neutron number

Number of neutrons used to build a nucleus.

Proton number

Proton number (atomic number) is the number of protons used to build a nucleus.

Mass of a neutron

The rest mass of a neutron is: $$ \class{brown}{m_{\text n}} ~=~ 1.674 \cdot 10^{−27} \, \mathrm{kg} $$

Mass of a proton

The rest mass of a proton is: $$ \class{brown}{m_{\text p}} ~=~ 1.672 \cdot 10^{−27} \, \mathrm{kg} $$

+ Perfect for high school and undergraduate physics students
+ Contains over 500 illustrated formulas on just 140 pages
+ Contains tables with examples and measured constants
+ Easy for everyone because without vectors and integrals

Learn more