digplanet beta 1: Athena
Share digplanet:

Agriculture

Applied sciences

Arts

Belief

Business

Chronology

Culture

Education

Environment

Geography

Health

History

Humanities

Language

Law

Life

Mathematics

Nature

People

Politics

Science

Society

Technology

Binding energy is the energy required to disassemble a whole system into separate parts. A bound system typically has a lower potential energy than the sum of its constituent parts — this is what keeps the system together. Often this means that energy is released upon the creation of a bound state. This definition corresponds to a positive binding energy. (This definition also often causes confusion. For example: A prominent term in chemistry is the 'free energy of binding', which is the difference between the bound and unbound states and thus negative).

General idea[edit]

In general, binding energy represents the mechanical work that must be done against the forces which hold an object together, disassembling the object into component parts separated by sufficient distance that further separation requires negligible additional work.

At the atomic level the atomic binding energy of the atom derives from electromagnetic interaction and is the energy required to disassemble an atom into free electrons and a nucleus. Electron binding energy is a measure of the energy required to free electrons from their atomic orbits. This is more commonly known as ionization energy.[1]

At the molecular level, bond energy and bond-dissociation energy are measures of the binding energy between the atoms in a chemical bond.

At the nuclear level, binding energy is also equal to the energy liberated when a nucleus is created from other nucleons or nuclei.[2][3] This nuclear binding energy (binding energy of nucleons into a nuclide) is derived from the nuclear force (residual strong interaction) and is the energy required to disassemble a nucleus into the same number of free, unbound neutrons and protons it is composed of, so that the nucleons are far/distant enough from each other so that the nuclear force can no longer cause the particles to interact.[4] Mass excess is a related concept which compares the mass number of a nucleus with its true measured mass.[5]

In astrophysics, gravitational binding energy of a celestial body is the energy required to expand the material to infinity. This quantity is not to be confused with the gravitational potential energy, which is the energy required to separate two bodies, such as a celestial body and a satellite, to infinite distance, keeping each intact (the latter energy is lower).

In bound systems, if the binding energy is removed from the system, it must be subtracted from the mass of the unbound system, simply because this energy has mass. Thus, if energy is removed (or emitted) from the system at the time it is bound, the loss of energy from the system will also result in the loss of the mass of the energy, from the system.[6] System mass is not conserved in this process because the system is "open" (i.e., is not an isolated system to mass or energy input or loss) during the binding process.

Mass-energy relation[edit]

Classically a bound system is at a lower energy level than its unbound constituents, and its mass must be less than the total mass of its unbound constituents. For systems with low binding energies, this "lost" mass after binding may be fractionally small. For systems with high binding energies, however, the missing mass may be an easily measurable fraction. This missing mass may be lost during the process of binding as energy in the form of heat or light, with the removed energy corresponding to removed mass through Einstein's equation E = mc2. Note that in the process of binding, the constituents of the system might enter higher energy states of the nucleus/atom/molecule, but these types of energy also have mass, and it is necessary that they be removed from the system before its mass may decrease. Once the system cools to normal temperatures and returns to ground states in terms of energy levels, there is less mass remaining in the system than there was when it first combined and was at high energy. In that case, the removed heat represents exactly the mass "deficit", and the heat itself retains the mass which was lost (from the point of view of the initial system). This mass appears in any other system which absorbs the heat and gains thermal energy.[7]

As an illustration, consider two objects attracting each other in space through their gravitational field. The attraction force accelerates the objects and they gain some speed toward each other converting the potential (gravity) energy into kinetic (movement) energy. When either the particles 1) pass through each other without interaction or 2) elastically repel during the collision, the gained kinetic energy (related to speed), starts to revert into potential form driving the collided particles apart. The decelerating particles will return to the initial distance and beyond into infinity or stop and repeat the collision (oscillation takes place). This shows that the system, which loses no energy, does not combine (bind) into a solid object, parts of which oscillate at short distances. Therefore, in order to bind the particles, the kinetic energy gained due to the attraction must be dissipated (by resistive force). Complex objects in collision ordinarily undergo inelastic collision, transforming some kinetic energy into internal energy (heat content, which is atomic movement), which is further radiated in the form of photons—the light and heat. Once the energy to escape the gravity is dissipated in the collision, the parts will oscillate at closer, possibly atomic, distance, thus looking like one solid object. This lost energy, necessary to overcome the potential barrier in order to separate the objects, is the binding energy. If this binding energy were retained in the system as heat, its mass would not decrease. However, binding energy lost from the system (as heat radiation) would itself have mass, and directly represents the "mass deficit" of the cold, bound system.

Closely analogous considerations apply in chemical and nuclear considerations. Exothermic chemical reactions in closed systems do not change mass, but become less massive once the heat of reaction is removed, though this mass change is much too small to measure with standard equipment. In nuclear reactions, however, the fraction of mass that may be removed as light or heat, i.e., binding energy, is often a much larger fraction of the system mass. It may thus be measured directly as a mass difference between rest masses of reactants and (cooled) products. This is because nuclear forces are comparatively stronger than the Coulombic forces associated with the interactions between electrons and protons, that generate heat in chemistry.

Mass change[edit]

Mass change (decrease) in bound systems, particularly atomic nuclei, has also been termed mass defect, mass deficit, or mass packing fraction.[citation needed]

The difference between the unbound system calculated mass and experimentally measured mass of nucleus (mass change) is denoted by Δm. It can be calculated as follows:

Mass change = (unbound system calculated mass) - (measured mass of system)
i.e., (sum of masses of protons and neutrons) - (measured mass of nucleus)

After nuclear reactions that result in an excited nucleus, the energy that must be radiated or otherwise removed as binding energy for a single nucleus may be in the form of electromagnetic waves, such as gamma radiation, or it may appear in the kinetic energy of an ejected particle, such as an electron, in internal conversion decay. Also, energy of excitation of nucleus can be partly emitted as the rest mass of one or more a particle, such as the emitted particles of beta decay. Again, however, no mass deficit can in theory appear until this radiation or this energy has been emitted, and is no longer part of the system.

When nucleons bind together to form a nucleus, they must lose a small amount of mass, i.e., there is mass change, in order to stay bound. This mass change must be released as various types of photon or other particle energy as above, according to the relation E = mc2. Thus, after binding energy has been removed, binding energy = mass change × c2. This energy is a measure of the forces that hold the nucleons together, and it represents energy which must be supplied again from the environment, if the nucleus were to be broken up into individual nucleons.

The energy given off during either nuclear fusion or nuclear fission is the difference between the binding energies of the "fuel", i.e., the initial nuclide(s), and the fission or fusion products. In practice, this energy may also be calculated from the substantial mass differences between the fuel and products, which uses previous measurement of the atomic masses of known nuclides, which always have the same mass for each species. This mass difference appears once evolved heat and radiation have been removed, which is a given requirement for measuring the (rest) masses of the (non-excited) nuclides involved in such calculations.

In 2005, Rainville et al. published a direct test of the energy-equivalence of mass lost in the binding-energy of a neutron to atoms of particular isotopes of silicon and sulfur, by comparing the new mass-change to the energy of the emitted gamma ray associated with the neutron capture. The binding mass-loss agreed with the gamma ray energy to a precision of ±0.00004 %, the most accurate test of E=mc2 to date.[8]

See also[edit]

References[edit]

  1. ^ IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version:  (2006–) "Ionization energy".
  2. ^ Brittanica Online Encyclopaedia - "nuclear binding energy". Accessed 8 September 2010. http://www.britannica.com/EBchecked/topic/65615/binding-energy
  3. ^ Nuclear Engineering - "Binding Energy". Bill Garland, McMaster University. Accessed 8 September 2010. http://www.nuceng.ca/igna/binding_energy.htm
  4. ^ Atomic Alchemy: Nuclear Processes - "Binding Energy". About. Accessed 7 September 2010. http://library.thinkquest.org/17940/texts/binding_energy/binding_energy.html
  5. ^ Krane, K. S (1987). Introductory Nuclear Physics. John Wiley & Sons. ISBN 0-471-80553-X. 
  6. ^ HyperPhysics - "Nuclear Binding Energy". C.R. Nave, Georgia State University. Accessed 7 September 2010. http://hyperphysics.phy-astr.gsu.edu/hbase/nucene/nucbin.html
  7. ^ E. F. Taylor and J. A. Wheeler, Spacetime Physics, W.H. Freeman and Co., NY. 1992. ISBN 0-7167-2327-1, see pp. 248-9 for discussion of mass remaining constant after detonation of nuclear bombs, until heat is allowed to escape.
  8. ^ Rainville, S. et al. World Year of Physics: A direct test of E=mc2. Nature 438, 1096-1097 (22 December 2005) | doi:10.1038/4381096a; Published online 21 December 2005.

External links[edit]


Original courtesy of Wikipedia: http://en.wikipedia.org/wiki/Binding_energy — Please support Wikipedia.
This page uses Creative Commons Licensed content from Wikipedia. A portion of the proceeds from advertising on Digplanet goes to supporting Wikipedia.
304307 videos foundNext > 

E=MC^2, Binding Energy and Mass Defect

http://www.aklectures.com/lecture/e-mc-2-binding-energy-and-mass-defect The website organizes the videos into clear and structured chapters that you can use ...

Binding Energy, Fission and the Strong Nuclear Force

Cassiopeia Project http://www.cassiopeiaproject.com/ St. Mary's Physics Online http://www.stmary.ws/highschool/physics/home/notes/modPhysics/ForcesInsideNucl...

Total Binding Energy of a Nucleus and Binding Energy per Nucleon

Topics: Calculate the total binding energy for Radon-222. The technique is to compare the total mass of the separated protons and neutrons to the mass of the...

Mass defect and binding energy

How to calculate the mass defect and binding energy for helium-4 More free lessons at: http://www.khanacademy.org/video?v=9b8qZ6OHZ5s.

Mass defect and binding energy (1)

Physics: Nuclear physics--mass defect and binding energy. This is a recording of a tutoring session, posted with the student's permission. These videos are o...

Binding Energy and Fission

This movie is part of the collection: Prelinger Archives Producer: Sutherland (John) Productions Sponsor: General Electric Company http://www.stmary.ws/highs...

Mass defect and Binding Energy

mass defect and binding energy and how this relates to Einstein's Famous formula.

Nuclear Binding Energy Calculation ; Mass Defect

this video uses E=mc^2 to determine the mass defect (mass difference) to calculate the nuclear binding Energy, E (energy difference). The nuclear binding ene...

HTPIB30O The Curve of Binding Energy

How to interpret the curve of binding energy per nucleon to predict which nuclei can release energy by fission, and which can by fusion. https://sites.google...

Physics - Nuclear Physics (6 of 22) Binding Energy of a Nucleus

Visit http://ilectureonline.com for more math and science lectures! In this video I will show you how to find the binding energy of a nucleus.

304307 videos foundNext > 

561 news items

 
Nature.com
Mon, 15 Dec 2014 09:45:19 -0800

A similar previous study7 was able to determine the binding energy of several states in homonuclear ytterbium dimers and to give evidence of their subradiant nature. What is truly remarkable in the present work is that the precision achieved now allows ...
 
Nature.com
Tue, 16 Dec 2014 22:56:12 -0800

The charge correction in the binding energy scale was performed by setting the –CH2– peak in the carbon spectrum to 285.0 eV. SiO2 nanoparticles were placed on a silicon wafer and dried under vacuum before XPS measurements. The morphology of the ...

Irish Examiner

Irish Examiner
Mon, 15 Dec 2014 16:56:15 -0800

The EU's established goal of reducing greenhouse-gas emissions by 40% by 2030 is supported only by non-binding energy-efficiency and renewable-energy targets. Devoid of true carbon-pricing reform, the deal depends on the EU's derelict Emissions ...

EurActiv

EurActiv
Wed, 15 Oct 2014 23:49:08 -0700

An ambitious, binding, energy efficiency target for 2030 should be backed not primarily to save energy or hit international goals, the letter said. A binding target was needed, “first and foremost to save jobs, competitiveness and the well-being” of ...
 
Huffington Post
Fri, 28 Nov 2014 15:32:40 -0800

Their patent application reads, in part, "Embodiments generate thermal energy by neutron generation, neutron capture and subsequent transport of excess binding energy as useful heat for any application." Andrea Rossi In 2011, Andrea Rossi, an Italian ...

Gizmodo

Gizmodo
Thu, 11 Dec 2014 11:30:00 -0800

And as we add another 70 percent to the Sun's mass, the additional mass will increase the binding energy of the mass that goes later, so that's underestimating it, too. But the real answer is not likely to be an order of magnitude more than 3e11 J/kg ...

EurActiv

EurActiv
Wed, 28 May 2014 09:46:22 -0700

Asked by EurActiv whether an energy savings goal should also be considered, Oettinger replied: “I feel that it would be appropriate to propose a binding energy efficiency target and make that proposal to the Council, and to the Parliament.” “Now more ...

Responding to Climate Change

Responding to Climate Change
Thu, 19 Jun 2014 06:03:30 -0700

A quarter of European Union member states say that they want a binding target for energy efficiency in 2030, in the run-up to a decision to be made by leaders in October. The EU executive, the European Commission, proposed in January deep cuts in ...
Loading

Oops, we seem to be having trouble contacting Twitter

Support Wikipedia

A portion of the proceeds from advertising on Digplanet goes to supporting Wikipedia. Please add your support for Wikipedia!

Searchlight Group

Digplanet also receives support from Searchlight Group. Visit Searchlight