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Question:

Calculate the molar binding energy of carbon-12 nuclei.

Attempt at solution:

I don't really know where to start with this. can someone explain some terms or background information for me? thanks.

- Thread starter Moe_slow
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- #1

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Question:

Calculate the molar binding energy of carbon-12 nuclei.

Attempt at solution:

I don't really know where to start with this. can someone explain some terms or background information for me? thanks.

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Kurdt

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so the mass of one proton is 1.0078 and neutron is 1.0086. there are six neutrons and 6 protons. that gives us 12.098940 and since the mass of the carbon 12 is 12.0000 the mass difference is 0.098940. insert that into einstien's equation and we get ((9.8x10^-5)(9.0x10^13))=8.9x10^9.

moving on. can you help me understand the concept of this question.

calculate the nuclear binding energy per nucleon. 4He 4.0026u.

i don't really understand the j/nucleon part or how to get there. i tried doing it similar to the other but get a wrong answer.

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Gokul43201

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Be careful with your units. Pay attention to the fact that 1.0078ok thanks. i think i understand.

so the mass of one proton is 1.0078 and neutron is 1.0086. there are six neutrons and 6 protons. that gives us 12.098940 and since the mass of the carbon 12 is 12.0000 the mass difference is 0.098940. insert that into einstien's equation and we get ((9.8x10^-5)(9.0x10^13))=8.9x10^9.

In the above case, you found the energy for 1 mole of nuclei - that's N(avogadro) nuclei. In this problem you want to find the binding energy for a single nucleon (4 nucleons in a nucleus, and N nuclei in a mole).calculate the nuclear binding energy per nucleon. 4He 4.0026u.

i don't really understand the j/nucleon part or how to get there. i tried doing it similar to the other but get a wrong answer.

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Astronuc

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For binding energy of He-4, consider mass of 2p and 2n and compare to mass of He-4. Then use that to calculate the binding energy. Divide by the number of nucleons in the He-4 nucleus (4) to get BE/nucleon.

Useful units. 1 u ( or atomic mass unit, amu) = 931.494 MeV = 1.660539 x 10

1 MeV = 1.6022 x 10

1.602 176 53(14) x 10

See - http://physics.nist.gov/cuu/Constants/index.html

See also Atomic and nuclear constants or use the values in one's textbook.

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