The binding energies per nucleon for deuteron (`_1H^2`) and helium (`_2He^4) are 1.1 MeV and 7.0 MeV respectively. The energy released when two deuterons fuse to form a helium nucleus (`_2He^4`) is

Explanation

The equation of fusion is reprersented as
`_.1H^2 +._1H^2 rarr ._2He^4 + "Energy"`
The binding energy per nucleon of deuteron is `1.1 MeV`. Therefore, the net initial binding energy `=4 xx 1.1 =4.4 Mev` The binding energy per nucleon of `._(2)He^(4)` is `7.0 MeV`. Therefore, the net final binding energy is
`4 xx 7.0 =28.0 MeV`
Hence, energy released `=28.0 MeV -4.4 MeV =23.6 MeV`.