Q. 525.0( 1 Vote )
Calculate the Q-value of the fusion reaction
4He + 4He = 8Be.
Is such a fusion energetically favorable? Atomic mass of 8Be is 8.0053 u and that of 4He is 4.0026 u.
Answer :
4He + 4He = 8Be.
Q value= [2m(4He)- m(8Be)]u
= [2×4.0026 – 8.0053] × 931MeV
=-93.1KeV
Negative sign indicates that the energy has to be provided to proceed this reaction. So, this fusion is not favorable.
Rate this question :






















Calculate the energy that can be obtained from 1 kg of water through the fusion reaction
2H + 2H →3H + p.
Assume that 1.5 × 10–2% of natural water is heavy water D2O (by number of molecules) and all the deuterium is used for fusion.
HC Verma - Concepts of Physics Part 2
The mass of a H-atom is less than the sum of the masses of a proton and electron. Why is this?
Physics - ExemplarIn pair annihilation, an electron and a positron destroy each other to produce gamma radiation. How is the momentum conserved?
Physics - ExemplarThe binding energy of a H-atom, considering an electron moving around a fixed nuclei (proton), is . (m = electron mass). If one decides to work in a frame of reference where the electron is at rest, the proton would be moving around it. By similar arguments, the binding energy would be
(M = proton mass)
This last expression is not correct because
Physics - Exemplar