Questions tagged [binding-energy]
Please use binding energy in the context of the atomic scale and/or atomic systems. This can be used in nuclear reactions.
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Why do elements heavier than calcium require more neutrons to remain stable? [duplicate]
In studying the periodic table, I noticed that calcium (with atomic number 20) is the heaviest element with stable isotopes with a 1:1 ratio of protons to neutrons. For elements heavier than calcium, ...
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Is the hydrogen atom heavier or lighter than the sum of individual particles? [duplicate]
I found a question in one of the exams (JAM-2005). I have attached the image to the question and related links. Wherever I found, the correct answer for the question is given as option (c). But isn't ...
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Understanding Feynman: why gravity is not a spin-0 theory?
I'm struggling to understand a certain paragraph in Feynman's "lectures on gravitation". It's lecture 3, why gravity cannot be a spin-0 theory. Here's the text:
The rejection of spin-zero ...
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Breakdown of the Fermi gas model for the nucleus
One of the predictions of the Fermi gas model for the nucleus is that the most energetically favorable situation for a nucleus is to have $N=Z$, an equal number of protons and neutrons. Observing the ...
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Are elements above 137 possible?
I have heard the argument that elements with atomic numbers above 137 are not possible but I am unsure if it's true or why.
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What is the atomic mass defect (or nuclear binding energy) of Iron-56 (Fe-56)?
It seems a simple enough calculation, but I keep getting 478.972467.... MeV.
Yet, Wikipedia insists on 492.275 MeV, and other sites give very similar numbers to Wikipedia's, not mine....
What am I ...
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Calculating Binding Energy of Th 230 nucleus [duplicate]
Ok this is NOT a homework question. But it’s somewhat related. Please bear with me.
In calculating BE of Th 230, I used the rest mass of proton as 1.007276u and rest mass of neutron as 1.008665u (as ...
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Can a big mass defect make the mass negative?
Can two particles with small masses and a strong attractive interaction have a total negative mass when brought together?
Let $m_1, m_2$ be the (rest) masses of two particles when infinitely distant. ...
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Why is the mass-energy graph for atomic mass $A=98$ not quadratic?
For fixed atomic mass $A$ and varying atomic number $Z,$ the mass of the nucleus is quadratic in $Z$. Were it possible for $Z$ to vary continuously, we'd have at most one local minimum. Since we are ...
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Why does the mass-energy equivalence apply to binding energy when it is derived purely through kinematic means?
I understand that by defining the four velocity, multiplying it by the rest mass and taking the entire thing's norm we get $E^2=m^2+p^2$, but how does this apply to binding energy, or in general ...
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Why does fission of large nuclei always result in energy released?
When large nuclei undergo fission, the binding energy per nucleon of products is greater than the binding energy of the original nuclei. This only happens (with certainty) when the products are Iron-...
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Why does binding energy of particles, which constitutes most of macroscopic mass, make them harder to accelerate?
I've seen a lot of questions on this topic so please don't misunderstand, I understand E = mc^2 and SEMF and so on. I specifically want to know how internal forces within lets say a nucleus make it ...
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Can electrons or protons due to fusion reduce in their individual mass?
It's a ridiculous question, but that's why I am asking it after getting confused over a paragraph about nuclear fusion in my textbook.
The total mass of a stable nucleus is slightly less than the ...
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Must a very large nucleus be spherical?
As we do know, residual nuclear force has short distance action so there is no total center to rim nuclear force aggregation inside the nucleus as in the case of for example gravitation in the case of ...
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Why does critical mass for radioactive isotopes seem to have little relation to half-life?
I understand that too short a half-life and flash point, becomes kind of meaningless, if the element generates too much heat, so this only applies to longer half-lives.
Also, as I understand it, flash ...
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Binding energy of Hydrogen = 0 = 13.6 ${\rm eV}$? [closed]
I was solving nuclear physics today.I used the binding energy formula on hydrogen.I found that B=0.But,B is also,as mentioned in my textbook,13.6eV. How?
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Is there proof for: "Elements heavier than iron will decay to iron by processes such as fission and alpha emission"?
Freeman J. Dyson in his "Time without end: Physics and biology in an open universe", Lecture 2: Physics, part G: All matter decays to iron, claimed that on a long enough time scale "...
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How can a proton be stable if binding energy *increases* it's mass? [duplicate]
A hydrogen atom weighs 13.6eV less than a proton + electron. This missing energy, which is tiny compared to the rest mass of almost a GeV, was carried off by a photon when the atom formed.
Nuclei show ...
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$Q$-value (nuclear)
I'm studying principles of physics.
I have a question.
In my book, they seem to have calculated the Q value in different ways.
$$
\begin{align}
\rm p + {^{27}_{13}Al} &\rightarrow \rm{^{27}_{14}Si}...
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Do orbits with positive energy tend to infinity?
Consider any potential field $$V = V(x)$$ (not limited to gravitational potential field, but we only consider time-independent ones) in 3-d space that satisfies the following conditions:
The ...
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If the fine-structure constant was very large could positronium have negative mass?
Positronium is an atom with one electron and one positron. It's mass is 1.022MeV which is almost twice the electron mass: The ground-state (1S orbital) binding energy of -6.8eV reduces the total mass ...
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Why is helium-4 the only nuclide with a negative nucleon binding energy?
He-4 is very unusual as it’s the only nuclide that does not accept another nucleon. In other words, even if you force a proton or a neutron into He-4, it will be kicked out immediately. If you ...
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What is the causation of the mass deficit in atomic nuclei?
I've always heard that when protons and neutrons are combined together into nuclei, the mass of the product is less than the mass of the constituents. And that this mass is called the mass deficit and ...
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Most stable isobar for even-$A$ nuclei
In the Liquid Drop Model of the nucleus, the most stable isobar is the one whose atomic number $Z_{A}$ is the one corresponding to the minimum mass, and can be found from the mass parabola or, by ...
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Why do nucleons pair up?
I'm learning about the semi-empirical mass formula currently, and in the explanation for the pairing term, the course notes say that it's energetically favorable for nucleons to pair up.
Could someone ...
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What is the real meaning of energy released in nuclear fission? [duplicate]
In a nuclear fission reaction the total energy and thus the mass of the products are lower than the total energy of the reactants. I understand the the difference in this energy can be used in a ...
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During fusion, how does mass turn into energy?
This is my (flawed) understanding of how fusion basically works:
Let's assume that a fusion reaction has a net gain in energy.
First, there is an input amount of kinetic energy to get the two light ...
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How is energy conserved in formation of chemical bonds?
I understand that when an H$_2$O molecule is formed, it has lesser total energy than the constituent (2H and O) atoms. I also understand that the potential energy (PE) will be reduced when the atoms ...
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Is the mass of Satellite + Earth system less than their individual masses?
I understand that when a Earth + Satellite system forms (satellite comes into orbit) the total energy is -ve. If the energy of the system when placed at infinity is 0 (assuming P.E and K.E is 0 at ...
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Why can't massive nuclei combine together to release energy
I am basically confused as why can't larger nuclei undergo fushion and release energy. One reason I know is because of too much protons than neutrons which generates stronger electrostatic repulsive ...
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Why is the nuclear binding energy per nucleon not constant at beginning?
I can understand, how it is constant after awhile, that due to the range of strong nuclear force the force is increasing linearly with the linear increase of the nucleon number, making it a constant.
...
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Negative Energy [duplicate]
I am uneducated on physics so please excuse my ignorance. I've been looking into negative energy which hasn't made much sense to me thus far. Through what I've read I think negative energy is simply ...
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Pairing term in semi-empirical mass formula and nature of spin-dependence of nuclear forces
I have a silly confusion. The Pairing term of the semi-empirical mass formula tells that nucleons tend to pair up. I believe that pairing up means forming a state in which two nucleons combine to give ...
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How the $N/Z$ ratio affects the stability of isotopes and their method of radioactive decay?
Although there is a graph that tells us the number of isotopes and which ones are stable or abundant in nature, like the one below, I have come across the $N/Z$ ratio, which is the number of neutrons ...
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Separation energy of nucleons and Coulomb barrier
My question is related to this topic: Tunneling of alpha particles. Unfortunately it didn't quite solve my doubts.
My professor and the book I'm reading (Particles and Nuclei: An Introduction to the ...
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Coulombian barrier fission
Protons and neutrons in a nucleus are both in a well of $\sim$ 50 MeV (obviously that depends on the specific nucleus), but the shape of the quantum well is different because there is the Coulomb ...
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Nuclear binding energy and gravitation
A nucleus $A$ can be split into two smaller nuclei $B$ and $C$. It is well known that the sum of the masses of $B$ and $C$ will not equal the mass of $A$ due to the nuclear binding energy and the ...
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The difference between neutron and proton separation energy of a nucleus
For a given nucleus, why does the value of the neutron separation energy $S_n$ differ from the value of the proton separation energy $S_p$? One of the reasons that is immediately obvious is that the ...
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Nuclear physics explained by QCD
I have been studying Particle & nuclear physics and I know that nuclear physics should normally be explained by particle physics. Specifically, I would like to ask if there is any theoretical ...
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Confusion about energy conservation for fusion and fission (binding energy and $Q$-value)
In a nuclear reaction, a system consisting of a nucleus or nuclei lose mass, and this mass gets turned into energy, which is quantified by $E=mc^{2}$. But I'm conceptually confused. According to ...
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Calculation of nuclear binding energy from atomic masses
The binding energy $B_\mathrm{nuc}(Z,N)$ of a nucleus of proton number $Z$ and neutron number $N$ satisfies
$$B(Z,N) = (Z\cdot m_p + N\cdot m_n - m_{\mathrm{nuc}}(Z,N)) \ [1], $$
where $m_p$ is the ...
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Why does the mass deficit exists? [duplicate]
Everyone knows Albert Einstein's famous formula: $E = m * c^2$
In nuclear fission, we make use of it by converting mass into energy.
But what is the mass that gets converted? Of course, when nuclei ...
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Binding energy vs Mass number Plot and Pairing effect for higher nuclei region
I have two doubts.
In every text or literature, one always see the graph of binding
energy per nucleon vs mass number and not binding energy vs mass
number. Is it like we don't interpret any useful ...
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Is there a way to determine whether a given nucleus is radioactive?
When a nucleus decays it is finding a more stable configuration, as all nature is. But is there a way of finding whether a specific configuration will decay?
I know that there is a specific proton-to-...
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How can negative potential energy cause mass decrease?
The mass of a hydrogen is less than its constituent parts(proton/electron). The explanation given for this is the following: Youtube
For hydrogen, $m = m_{components} + m_{extra}$ where we can write $...
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Why is U-238 detrimental for nuclear bomb？
I know U-238 is more stable than U-235, because it is an even-even nucleus. Only neutron with energy larger than 1.6Mev can split an U-238, while any neutron can split U-235.
But why is the presence ...
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What happen with missing energy conserved as mass in decay $\rm {}^4H\to {}^3H + n$?
What happen with missing energy conserved as mass in decay $\rm {}^4H\to {}^3H + n$?
https://en.wikipedia.org/wiki/Isotopes_of_hydrogen
$${}^4H \leftrightarrow {}^3H + n$$
$$4.02643 > 3....
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Why we can take for granted that energy binding is associated with inertial mass?
It is common to state that a proton is bounded state of three quarks, and that the QCD energy binding (associated to a "cloud" of gluons joining together the three quarks) is responsible for ...
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In what form is the binding energy released after nuclear fission?
This is too primitive question. but I cant find a definitive answer anywhere.
Everywhere its mentioned that Binding energy is released in the good-ol uranium 235 and uranium 238 nuclear fission.
Where ...
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In a fission reaction mass is converted to energy my students are asking where the mass is taken from - do the nucleons have less mass afterwards? [duplicate]
I am teaching year 11 Physics for the first time. In a fission reaction mass is converted to energy my students are asking where the mass is taken from - do the nucleons have less mass afterwards?
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