Can a nuclear reaction violate the first law of classical thermodynamics?

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Nuclear reactions do not violate the first law of thermodynamics; instead, they illustrate the need to unify the laws of conservation of mass and energy as established by Einstein's theory of relativity. Before this unification, classical thermodynamics treated mass and energy as separate entities, leading to apparent violations during nuclear processes. The discussion highlights the importance of understanding that mass-energy equivalence (E=mc^2) allows for a comprehensive conservation law. The argument centers on the interpretation of classical versus modern thermodynamics, emphasizing the evolution of scientific understanding. Ultimately, the consensus is that nuclear reactions are consistent with the first law when viewed through the lens of modern physics.
Felgar
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Hi Guys,

I'm in an argument with someone on another forum (car forum no less) and he refuses to accept that nuclear reactions break the first law of classical thermodynamics. I'm only trying to show him that before energy and mass were shown to be interchangeable, the laws of conservation energy and of conservation of mass is the classical sense are violated by nuclear/radioactive processes. However, it's so commonly accepted now that mass-energy is conserved together rather than seperately, I can't find a valid and credible source that distinguishes between classical and more modern thermodynamics.

Can anyone help with a link? Thanks guys.
 
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I am not aware of nuclear reactions breaking any laws of thermodynamics.
 
Just that taken separate from each other, the laws of conservation of mass and conservation of energy don't hold, because we'll lose mass in a nuclear reaction. Not until the revelation that e=mc^2 and the combination of the two laws do we actually get a conservation law that is not broken.

quoted from
Relativity, the Special and General Theory
by Dr. Einstein

"Before the advent of relativity, physics recognized two conservation laws of fundamental importance, namely the law of conservation of energy and the law of the conservation of mass; these laws appeared to be quite independent of each other.
By means of the theory of relativity they have been united into one law... "
 
You shouldn't see this as a violation of the 1st law of thermodynamics, you should rather consider that in the first law, energy can now (since Einstein) include what is available through E = mc^2 in the case where you have nuclear reactions.
 
Alrighty then... No wonder it was hard to find that reference. Heh.

And yeah, obviously that's what makes the most sense. But the argument was about the classical definition which I was arguing wuold have to be observed in the strictest sense. But yeah, whatever.
 
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