Correct statement regarding nuclear reactions

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songoku
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Homework Statement
Which of the following statements is correct?
a. If the total mass of the product of a reaction is greater, this reaction is impossible
b. When a stationary nucleus decays to produce a daughter nucleus and a gamma photon, the products always move off in opposite direction
c. The greater the binding energy of a nucleus, the more stable it is
d. although the half life of a radioactive substance is unaffected by changes in pressure, we can still change the half - life by allowing the substance to react chemically to produce a new radioactive compound
Relevant Equations
Not sure
Option A is wrong because the reaction is still possible but just can not happen spontaneously?

Option B is correct

Option C is wrong because it should be binding energy per nucleon

Option D is wrong because it should be nuclear reaction instead of chemical reaction?

Thanks
 
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"When a stationary nucleus decays to produce a daughter nucleus and a gamma photon, the products always move off in opposite direction"

Is it possible that those are the only products of the decay? (I really do not know... never studied this.)
 
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haruspex said:
"When a stationary nucleus decays to produce a daughter nucleus and a gamma photon, the products always move off in opposite direction"

Is it possible that those are the only products of the decay? (I really do not know... never studied this.)

Maybe in this question it is assumed only these two products are produced by the decay so they need to move in opposite direction so the momentum is conserved
 
songoku said:
Maybe in this question it is assumed only these two products are produced by the decay so they need to move in opposite direction so the momentum is conserved
Maybe.. or maybe you are supposed to realize there have to be other products, in which case...
 
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haruspex said:
Maybe.. or maybe you are supposed to realize there have to be other products, in which case...
At first, I was sure that B is the correct answer. Are you saying that it is not correct?
 
songoku said:
At first, I was sure that B is the correct answer. Are you saying that it is not correct?
As I wrote, I am no expert on the topic, and was not aware of a decay mode that only has those two products. Since you seem unsure, I just Googled it. I now see there is a flavour of gamma decay that does just that, so I agree with option B.
 
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Thank you very much
 
By the way @haruspex, are my reasoning for option A and D correct?
 
haruspex said:
The answers are correct, but your reasoning for D could be a bit more convincing.
Sorry but I do not know other more correct reasoning for option D
 
haruspex said:
Try to explain why a chemical reaction would not alter the half life. What determines the half life?
Sorry, I am not sure. I always think the value of half life is constant
 
I am sorry for late reply

Sorry I do not know. Maybe it depends on mass and atomic number of the nuclei?

Thanks
 
haruspex said:
Quite so. And do either of those change in a chemical reaction?
I get it. Thank you very much haruspex