Completion of radioactivity equation

In summary: It seems your book is skipping intermediate steps as well, since the reaction should produce boron-12, or more likely boron-11 which would be a fusion reaction releasing a neutron, which despite being stable, then beta decays to carbon-11, which is unstable.Methinks you might want to tell the professor that the reactions and decays in the book are not realistic.But, yes, that would have to be the result of that problem.The typical reaction for neutron bombardment of beryllium is:Be-9 + neutron yields 2 He-4 + 2 neutrons.meaning beryllium acts as a neutron multiplier.
  • #1
mstud
69
0

Homework Statement



Complete this reaction equation:
[tex]^9_4 Be + ^1_0 n \rightarrow ^4_2 He + ?[/tex]

Homework Equations



Not relevant

The Attempt at a Solution



I find the answer to be [itex]^6_2 He[/itex] , but the answer key in my book says [itex]^7_3 Li[/itex]

I can't see how that can be right, please help!
 
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  • #2
mstud said:

Homework Statement



complete this reaction equation:
[tex]^9_4 be + ^1_0 n \rightarrow ^4_2 he + ?[/tex]


Homework Equations



not relevant

The Attempt at a Solution



i find the answer to be [itex]^6_2 he[/itex] , but the answer key in my book says [itex]^7_3 li[/itex]

i can't see how that can be right, please help!

[tex]^9_4 be + ^1_0 n \rightarrow ^3_1 H + ?[/tex]

If the first "product" was in fact Tritium, I could understand the Lithium, other wise your conjecture seems appropriate.
 
  • #3
Considering neutron absorption by Be-9 produces Be-10 which decays by beta to B-10, I think the book may be wrong.
 
  • #4
I think everyone can agree that helium-6 does not exist as a possible end product.
 
  • #5
I know that's an impossible nuclide, (it won't exist) , but that only indicates my book must contain an error in that problem. Thanks for settling that matter ! :approve:

Here's a similar one, which also gives me a somewhat strange answer:

[tex]^{10}_4 Be + ^2_1 H \rightarrow X + ^{11}_6 C[/tex]

The X must then be: [itex]^1_{-1} X[/itex]. :rofl: As far as I know this is not a common particle, but it might be here that the X stands for one neutron and one electron, that is [itex]^1_0 n + ^0_{-1} e[/itex].

What do you think?
 
  • #6
It seems your book is skipping intermediate steps as well, since the reaction should produce boron-12, or more likely boron-11 which would be a fusion reaction releasing a neutron, which despite being stable, then beta decays to carbon-11, which is unstable.

Methinks you might want to tell the professor that the reactions and decays in the book are not realistic.

But, yes, that would have to be the result of that problem.
 
  • #7
The typical reaction for neutron bombardment of beryllium is:

Be-9 + neutron yields 2 He-4 + 2 neutrons

meaning beryllium acts as a neutron multiplier.

See: http://en.wikipedia.org/wiki/Beryllium
 
  • #8
daveb said:
It seems your book is skipping intermediate steps as well, since the reaction should produce boron-12, or more likely boron-11 which would be a fusion reaction releasing a neutron, which despite being stable, then beta decays to carbon-11, which is unstable.

Methinks you might want to tell the professor that the reactions and decays in the book are not realistic.

But, yes, that would have to be the result of that problem.

Well, yes, maybe my book is written to oversimplify some things ... then the reactions and decays most probably can't become realistic. Maybe I should find a book describing the intermediate steps as well, which I can read beside the curriculum, so I'll know more often what these steps are like. Any suggestions for a good book on this topic? (I'm sitting in a library right now today, so I might be able to find it here)

Many thanks for checking my answer !
 
  • #9
If you mean a book that shows the normal modes of decay and their end products, the Chart of Nuclides published by Knolls Aomic Power Lab (KAPL) is what I use.
 

What is the purpose of completing a radioactivity equation?

The completion of a radioactivity equation allows scientists to accurately measure the amount of radioactive material present in a sample. This is important for studying the decay rate of a substance and understanding its potential impact on the environment or human health.

What is the general format of a completed radioactivity equation?

A completed radioactivity equation typically consists of the radioactive element or isotope, the decay mode, the product of the decay, and the resulting equation. For example, the equation for the alpha decay of uranium-238 is:
23892U → 4He + 23490Th

How do you balance a completed radioactivity equation?

To balance a completed radioactivity equation, the total number of protons and neutrons on both sides of the arrow must be equal. This can be achieved by adjusting the coefficients (numbers in front of each element or isotope) until the equation is balanced. The number of protons and neutrons should be the same on both sides, as well as the atomic mass.

What is the significance of the half-life in a completed radioactivity equation?

The half-life is the amount of time it takes for half of a radioactive substance to decay. It is an important factor in understanding the rate of decay and determining the amount of a substance present at a certain point in time. The half-life can also be used to calculate the age of a sample or the amount of time it will take for a substance to become non-radioactive.

Why is it important to use proper units when completing a radioactivity equation?

Using proper units, such as mass or moles, is crucial in accurately completing a radioactivity equation. This ensures that the equation is balanced and that the correct measurements are being used. It also allows for easier comparison and analysis of different samples and their levels of radioactivity.

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