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.

Filter by
Sorted by
Tagged with
1 vote
2 answers
50 views

Why does a tritium nucleus have a higher mass than $^3\rm He$?

$^3\rm He$ has a lower (nuclear) mass than tritium which is why the latter decays into the former. This is not explained by the semi-empirical mass formula, which would predict a lower binding energy (...
  • 675
0 votes
1 answer
40 views

Mass from the Higgs mechanism vs the chromodynamic binding energy

I heard recently that the Higgs field gives most of the Standard Model particles their masses. However, I remember reading about the chromodynamic binding energy and that this was the primary source ...
1 vote
3 answers
61 views

Why can protons and neutrons be close together in a nucleus despite the uncertainty principle?

Vol II, Chapter 1 of the Feynman Lectures explains why negative electrons do not get closer to the positively charged nucleus despite the great attractive force: If we try to confine our electrons in ...
0 votes
0 answers
33 views

General Half-life calculation for an abitrary nucleus

I have been getting back into physics and I was wondering whether there was a generalized half-life equation for any given nucleus composition. For instance for gold isotope 210-AU. Is it possible to ...
1 vote
2 answers
47 views

About binding energy, mass defect and enegy released in a nuclear fusion

I know this question looks very similar to many others but I actually think it is not the same, because I was looking for a possible answer for hours. The question is about the first step in the pp ...
0 votes
0 answers
25 views

Why we have not observed one proton and one neutron nuclear decay? [duplicate]

I'm learning about nuclear decays: Alpha (helium nucleus, +2) Beta (electron) Gamma (photon) Neutron But why helium nucleus? Why not hydrogen nucleus (deuterium)? I mean why two protons and two ...
0 votes
0 answers
23 views

Is an element necessarily more stable if the no. of protons and neutrons are equal? [duplicate]

This question came in the Rajshahi University admission exam 2017-18 Q) An element is more stable if in its atom- (a) Protons and neutrons are equal in number (b) Protons and electrons are equal in ...
0 votes
1 answer
57 views

Is mass defect of atoms considered when the mass of electron is measured within atoms?

First of all, here considering the mass defect as the binding energy between an electron and the rest of the atom; i.e. taking the mass of nucleus as it is. That since nuclear mass defect is present ...
  • 77
0 votes
1 answer
33 views

Why $\rm Ag$ 108 decays into $\rm Cd$ 108 most of the time?

In the table of nuclides, it shows that $\rm Ag$ 108 can go through either electron capture or beta- decay (though the branching ratio for electron capture decay is much lower). What determines that? ...
0 votes
0 answers
22 views

Tightly bound energy configuration for nucleons?

In fusion, why are nucleons of the product nucleus tightly bound and in a lower energy configuration than the nucleons in the reactant nuclei? I think the reason a large amount of energy is released ...
2 votes
5 answers
408 views

Why does binding energy cause mass defect?

During fusion, for instance hydrogen fuse to form a helium nucleus which has lower mass than the sum of its constituents.... Why is it so? I have read that energy is required to break apart the ...
0 votes
1 answer
99 views

Calculating the Energy released in Fusion between Deuterium and Tritium

I'm trying to calculate the Energy you would get in a fusion reactor from the fusion of deuterium and tritium: ${}^2H+{}^3H \rightarrow {}^4He + n$ Using this Equation: $E = E_{rest} + E_{kin} = mc^2 +...
-1 votes
2 answers
88 views

$E=mc^2$ in particle physics vs non-relativistic quantum mechanics (NRQM)

I have seen in many places that the equation $E=mc^2$ is useful for describing subatomic particles as well, and, this is the basis of Nuclear reaction. However, to my understanding, this equation is ...
1 vote
0 answers
40 views

Negative potential energy

In fusion of hydrogen into helium, hydrogen has negative potential energy which adds up and results in a mass defect.. Doubts:- Why is there negative potential energy between the nucleons in a ...
  • 21
0 votes
1 answer
50 views

Cause of energy release in fusion [duplicate]

For the fast few months, I have been scratching my head for this problem which I have faced while studying fusion. In a hydrogen fusion, two hydrogen (for instance ) fuse to form a helium nucleus. I ...
81 votes
2 answers
7k views

Why doesn't a nucleus-like body made up of just neutrons exist?

We know that neutrons exert short ranged nuclear forces over other nucleons in a nucleus, and these forces are only attractive in nature. Also this force is universal and doesn't differentiate between ...
  • 783
1 vote
4 answers
108 views

Why is some mass converted into energy when neutrons and protons combine to form nucleus?

So some of the mass is converted into energy when neutrons and protons combine to form nucleus. Why? And how? And then why do we need to supply the same amount of energy to separate them?
1 vote
2 answers
118 views

Nuclear fusion mass defect and energy production

In researching the topic of nuclear fusion, I have a few doubts related to the mass defect, 'negative' potential energy and resultant energy released as a by-product of nuclear fusion. When two ...
11 votes
3 answers
3k views

What happens when the universe runs out of fuel?

After some X billion years, one would think the stars in the entire universe will run out of hydrogen. What would happen next? Is there any way to get hydrogen out of heavy metals (extreme fission)? ...
  • 720
3 votes
2 answers
907 views

Why do elements, as they have more protons, need a higher amount of neutrons to stabilise them? [duplicate]

I've seen the graphs of the stability line but I can't find any reason as to why this happens, I understand radiation, just not why radiation needs to occur in the first place if that makes sense.
0 votes
1 answer
41 views

Fusion energy origin

In fusion , I have understood so far that two light nuclei fuse to form a heavy nucleus. The nucleons in the light nuclei experience lesser binding energy as compared to the nucleons in heavy nucleus ...
0 votes
1 answer
50 views

Why does the stability of a nucleus depend on the binding energy $\textit{per nucleon}$ instead of the total binding energy?

The larger the total binding energy of a nucleus, the greater the minimum energy that must be added to infinitely separate the constituent nucleons. Shouldn't the total binding energy, then, be used ...
1 vote
1 answer
77 views

In general relativity, assuming a spherical uniform mass distribution, what is the total energy value of the gravitational field inside the sphere?

In Newtonian mechanics, assuming a spherical uniform mass distribution, the total gravitational potential energy (gravitational self-energy) inside the sphere is $$U_{gs}=-\frac35\frac{GM^2}R.$$ In ...
  • 109
0 votes
0 answers
31 views

How can a proton in a nucleus decay into neutron and positron in β+ decay if neutrons have greater mass than a proton? [duplicate]

I'm guessing it has something to do with mass defect/binding energy??
0 votes
0 answers
49 views

Inertial properties of negative masses

Pondering Casimir effect and negative mass and Gravitational binding energy as alternative to dark matter? I start to think that each form of negative energy has negative gravitational mass. The list ...
28 votes
6 answers
4k views

How is Alpha Radiation possible?

Alpha radiation would seem to occur when a pair of protons and neutrons are magically plucked from the amorphous (i.e. having no particular structure) nucleus of a heavier atom. Some of the problems ...
  • 313
3 votes
1 answer
98 views

What determines the half-life (or stability) of an isotope?

Why is it that some elements do not have any stable isotopes, while others of very similar mass have multiple stable isotopes? What determines this phenomenon and what determines the strict ...
  • 133
1 vote
0 answers
75 views

Derivation of the Binding Energy of Atoms without Kinetic Considerations and Relativistic Corrections

The question Relativistic corrections to the binding energy of atoms is answered with a brief chronology of ideas about the binding energy of the electron to the atomic nucleus. (The emphasis in the ...
1 vote
1 answer
79 views

Relativistic Corrections to the Binding Energy of Atoms

The binding energy of atoms is the minimum energy required to remove an electron of an atom from its orbital. Using dimensional analysis, we can derive the following equation. $$E_B\propto\frac{m(ke^2)...
1 vote
0 answers
31 views

Xe-135 Binding Energy - Calculations Not Agreeing With Reported Values

I am trying to calculate the binding energy of Xe-135 using the following equation: \begin{equation} BE = \Delta{}c^2 \end{equation} Where $\Delta{}$ is the mass defect: \begin{equation} \Delta{} = ...
0 votes
1 answer
142 views

When calculating the $Q$-value of a reaction, does the energy released by gamma rays need to be considered?

In certain reaction, gamma rays are released as products. Take the following reaction for example: $${}^1_{0}n + {}^{235}_{92}U \rightarrow {}^{140}_{54}Xe+{}^{94}_{38}Sr + 2{}^{1}_{0}n + \gamma(6MeV)....
0 votes
2 answers
243 views

Why electrons in orbitals have negative energy?

The potential energy of electron is negative so; kinetic $+$ potential $= \ \ -$energy ; but the kinetic energy gets lower as an electron is farther from nucleus; needs less acceleration to orbit I ...
0 votes
0 answers
23 views

Nuclear physics questions [duplicate]

Why the mass of nuclues is smaller than the individual mass of nucleon which is the mass of individual subatomic particle? Why is there a missing energy?
0 votes
0 answers
28 views

Mass defect and nuclear binding energy

Nucleons bound in the reactant nuclei have low binding energy and when they fuse together , the nucleons are bound more tightly as coloumb force is also increasing. Since energy is required to tightly ...
0 votes
0 answers
67 views

Why is there destructive interference in an atom between protons and electrons?

"In energy wave theory, Planck’s relation describes the energy of a transverse wave, emitted or absorbed as an electron transitions energy levels in an atom. When an electron is contained within ...
0 votes
1 answer
73 views

$Q$ values for 3 types of beta decays

For the three types of beta decay: \begin{align} _z^AP&\rightarrow {}_{z+1}^AD + e^-+\bar{\nu} & Q_{\beta^-} &= (M_P-M_D)c^2 \\ _z^AP&\rightarrow {}_{z-1}^AD + e^++{\nu} & Q_{\beta^...
  • 409
1 vote
2 answers
69 views

On non-existence of molecular helium (and or why that's equivalent to bond order zero)

Why does molecular orbital theory (MOT) imply that molecular helium does not exist? All answers I found in the web use following two standard arguments, but I not see why these are sufficient to ...
  • 89
1 vote
1 answer
109 views

Why is the isotope Lithium 6 stable against alpha decay?

According to the table the binding energy of Helium 4 is 7.073915MeV/Nucleon while the binding of Lithium 6 is 5.606291MeV/Nucleon. So why is the lithium 6 isotope not an alpha particle emitter? I ...
0 votes
1 answer
48 views

When nucleons are assembled in form of nucleus is some mass lost? [duplicate]

We are told that $B.E = [Zm_p + Nm_n - M] c²$ Here, Z = Atomic no. ,$m_p$ = mass of proton, $m_n$ = mass of neutron and M = Mass of nucleus. Because if the mass is not lost then the energies should ...
43 votes
10 answers
11k views

Why can atoms only gain or lose electrons and not protons?

I know that an object can become net negative or net positive by losing or gaining electrons, and having more or fewer protons than electrons but why can't protons be transferred too?
0 votes
1 answer
37 views

Converting between mass and binding energy in semi-empirical mass formula

The semi-empirical mass formula is given in terms of the binding energy as: $$ B(Z,N) = aA - bA^{\frac{2}{3}} - s \frac{(N-Z)^{2}}{A} - d \frac{Z^2}{A^{\frac{1}{3}}} - \frac{\delta}{A^{\frac{1}{2}}}$$ ...
  • 129
1 vote
1 answer
72 views

How does moving an electron to a higher level actually work?

I understand the photoelectric effect and I assumed until an hour ago that to excite an electron, the photon should have energy equal to the binding energy of the initial level plus the binding energy ...
2 votes
0 answers
66 views

How weak are the Van der Waals bonds? What is their contribution to the total mass of an object?

We know that every binding energy can be expressed as a negative mass contribution to the total mass of the system. It is well known, for example, that composite nuclei have a “mass defect” when ...
  • 877
0 votes
0 answers
21 views

Why is internal energy of nucleons ∝ to binding energy? [duplicate]

In fusion , as two light nuclei fuse , the relative binding energy experienced by each nucleon is increased and hence the internal energy of the nucleons is decreased which by E=mc² causes a decrease ...
0 votes
0 answers
29 views

Nuclear binding and internal energy [duplicate]

A section of some article: When you cool a body at rest its internal energy decreases. Since energy is related to mass, here $E=m_0c^2$, where $m_0$ is the rest mass, the rest mass of the body ...
1 vote
3 answers
149 views

Strong nuclear force in fusion

I have read that there is an increase in the amount of the binding energy from the reactant nuclei and the product nucleus during nuclear fusion and this causes the decrease the internal energy (...
4 votes
5 answers
193 views

Why do two hydrogen atoms bond?

I was wondering (with my limited classical physics knowledge) why two hydrogen atoms tend naturally to a bonding configuration, I mean, given two hydrogen atoms with zero relative velocity between ...
  • 41
1 vote
3 answers
274 views

Why is energy released when nucleons come together to form a nucleus?

Binding energy is defined as the energy required to split a given nucleus into it's individual protons and neutrons. But why when nucleons are combined they release energy? What is the origin of this ...
5 votes
2 answers
300 views

Gravitational binding energy as alternative to dark matter?

Pondering this question: Casimir effect and negative mass and, in particular, the response of John Rennie "as the mass of any bound system is slightly less than the mass of its parts" I ...
12 votes
2 answers
201 views

Why there is no reaction Deuterium + Deuterium $=\rm {}^{4}He$?

Why there is no reaction like $D+D={}^{4}He$ specified here and in other places like this? Apparently $2\times2.0141-4.0026=0.0256$ is positive. What is the problem with this reaction?
  • 1,636

1
2 3 4 5
9