Name the unit which is commonly used for expressing the energy released in nuclear reactions.

Million electron volt (MeV) is the unit that is commonly used for expressing the energy released in nuclear reactions.

Explanation

The energy released in nuclear reactions is expressed in the unit of 'electron volt' (eV) or 'million electron volt' (MeV), where 'electron volt' is a small unit, whereas 'million electron volt' is a bigger unit. Therefore the energy released in nuclear reactions is usually expressed in terms of million electron volts.