2 Calculate the energy equivalent of 1 g of substance Solution
Energy, E = 10–3  × ( 3 × 108)2 J
     E = 10–3 × 9 × 1016 = 9 × 1013 J
Thus, if one gram of matter is converted to energy, there is a release
of enormous amount of energy Experimental verification of the Einstein’s mass-energy relation has
been achieved in the study of nuclear reactions amongst nucleons, nuclei,
electrons and other more recently discovered particles In a reaction the
conservation law of energy states that the initial energy and the final
energy are equal provided the energy associated with mass is also
included