Enter the mass of the initial reactants and the mass of the products after the nuclear reaction to estimate the energy released from fission.

Fission Reaction Energy Release Calculator

By Fuel Mass
By Mass Defect (E=mc²)

Enter how much fuel you have — get the total energy released if it all undergoes fission.

Fission Reaction Energy Release Formula

The following equation is used to calculate the Fission Reaction Energy Release.

Ef = (Mi-Mf)*c^2
  • Where Ef is the energy released from fission (J)
  • Mi is the initial mass of the reactants (kg)
  • Mf is the final mass of the products after the reaction (kg)
  • c is the speed of light in vacuum (299,792,458 m/s)

To calculate the energy released from a fission reaction, multiply the change in mass by the speed of light squared (c²).

What is Fission?

Definition:

Fission is a nuclear process in which the nucleus of a heavy atom splits into two (or occasionally more) lighter nuclei, typically releasing free neutrons and gamma rays (photons). This is accompanied by the release of large amounts of energy because the products have a higher total binding energy than the original nucleus.

In reactors, fission is usually induced when a nucleus absorbs a neutron and becomes unstable; it does not require extremely high temperatures (unlike fusion). The process involves a balance between the attractive strong nuclear force (which binds nucleons together) and the repulsive Coulomb force between protons.

Fission chain reactions are used to generate power in nuclear reactors and in fission weapons; in thermonuclear weapons, a fission “primary” provides energy and neutrons to initiate fusion. Most fissions are binary (two main fragments), but about 0.2% are ternary fissions in which a light charged particle (often an alpha particle) is emitted in addition to the two main fragments.

How to Calculate Fission Reaction Energy Release?

Example Problem:

The following example outlines the steps and information needed to calculate Fission Reaction Energy Release.

First, determine the initial mass of the reactants. In this example, the initial mass is found to be 10.00345 kg.

Next, determine the final mass of the products after the reaction. For this problem, the final mass is 10.00211 kg.

Finally, calculate the energy release using the formula above:

Ef = (Mi-Mf)*c^2

Ef = (10.00345-10.00211)*299,792,458^2

Ef = 1.20433194e14 Joules