Find the energy equivalent of one atomic mass unit, first in joule and then in MeV. Using this, express the mass defect of `._8O^(16)` in Me`V//c^2`. Given `M_(p)=1.007825u` and `M_(n) =1.008665 u, m_("oxy")=15.99053` a.m.u. and Take `1 a.m.u=933.75MeV//c^2`.

Explanation

`lu=1.6605xx10^(-27)kg`
To convert it into energy units, we multiply it by c2 and find that energy equivalent `= 1.6605 × 10^(–27) × (2.9979 × 10^(8))^(2) kg m^(2)//s2`
`=1.4924xx10^(-10)J`
`=(1.4924xx10^(-10))/(1.602xx10^(-19))eV`
`=0.9315xx10^(9)eV`
`=931.5 MeV`
or,`lu=931.5MeV//c^(2)`
For `._(8)^(16)O,DeltaM=0.13691u=0.13691xx931.5 MeV//c^(2)`
`=127.5MeV//c^(2)`
The energy needed to separate `._(8)^(16)O` into its constituents is thus`127.5 MeV//c^(2)`.