2
votes
4answers
103 views

Why do almost all nuclear reactions release energy?

I'm just wondering why almost all nuclear reactions release energy, in a typical way, the mass defect is transformed into energy ? Is there a nuclear reaction that gains mass (resp. energy)? or most ...
3
votes
2answers
354 views

Why can't Iron fusion occur in stars?

It is said that iron fusion is endothermic and star can't sustain this kind of fusion (not until it goes supernova). However star is constantly releasing energy from fusion of elements like Hydrogen ...
4
votes
0answers
66 views

How fission and fusion create energy? [duplicate]

Possible Duplicate: How to explain $E=mc^2$ mass defect in fission/fusion In order for energy to be released, mass has to be "lost", because mass is a form of energy. In my science class, ...
5
votes
1answer
3k views

How to explain $E=mc^2$ mass defect in fission/fusion

What is the nature of nuclear energy? This is closely related to the correct explanation of mass defect. I did some research of that topic and cannot come to a single comprehensive and consistent ...
7
votes
2answers
385 views

What elements can be created in the fusion process of different types of stars?

As I understand it fusion inside a sun can produce heavier and heavier elements until some sort of "nucleus size limit" is reached. As far as I understand, the limit is thought to be reached with the ...