Posted on 01/26/2007 5:55:38 AM PST by randita
Yes, and I understand about Planck's thinking on binding energies. But atomic reactions are not part of combustion in and internal combustion engine, the point of this discussion. What matter do you believe is converted to energy during the burning of ethanol?
--Yes, and I understand about Planck's thinking on binding energies. But atomic reactions are not part of combustion in and internal combustion engine, the point of this discussion. What matter do you believe is converted to energy during the burning of ethanol?--
I don't think you understand Plank's thinking and about binding energies or you wouldn't be asking that question.
A bushel of corn used as ethanol feedstock will yield 17 lbs. of distillers dried grains. What nutrients do you expect to find in the corn, other than sugar, that you wouldn't find in the DDG's?
My understanding of Planck's thinking is rather basic and limited, I will admit. I'm curious why you won't answer what matter you believe is converted to/from energy during the combustion of ethanol.
Until our energy infrastructure is based on matter-antimatter reactions, don't you think we can safely ignore mass-energy equivalence considerations?
I'm barely scratching the surface of "Thermochemistry for Dummies" here.
http://research.amnh.org/~tyson/18magazines_inthebeginning.php
Interesting, but gamma-ray photons and quarks are not involved in the combustion of ethanol.
What matter do you believe is converted to/from energy during the combustion of ethanol?
--My understanding of Planck's thinking is rather basic and limited, I will admit. I'm curious why you won't answer what matter you believe is converted to/from energy during the combustion of ethanol.--
I have given you several links. Here is one that is straight forward, at least in the beginning before it gets to the equations and graphs. OTOH, as a engineer, you should have seen these before, unless you are a civil.
http://en.wikipedia.org/wiki/Binding_energy
The mass of a body is a measure of its energy-content; if the energy changes by E, the mass changes in the same sense
It doesn't get much plainer than that!
From my link in 89:
Since all forms of energy in a system (which has no net momentum) have mass, the question of where the missing mass of the binding energy goes is of interest. The answer is that this mass does not "disappear" into energy (a common misconception); rather, transformed to heat or light, this mass may move away to another location. The "mass defect" from binding energy is therefore only mass which has moved. However, it remains mass, because mass is conserved in systems for any given single observer, so long as the system remains closed. Thus, if binding energy mass is transformed into heat, the system must be cooled (the heat removed) before the mass-deficit appears in the cooled system. In that case, the removed heat (which has mass itself when measured in the original inertial frame) represents exactly the mass "deficit."
For example, when two large objects (such as the earth and a meteor) are attracted by a gravitational field and collide, the energy for the heat of impact is extracted from the gravitational field of the objects. However, the system does not lose mass (which represents its binding energy) until this heat is radiated into space, and this space is no longer counted as part of the original system (equivalent to opening the original system).
Closely analogous considerations apply in chemical and nuclear considerations. However, in nuclear reactions, the fraction of mass which may be removed as light or heat, and which then appears as binding energy, is often a much larger fraction of the system mass. This is because nuclear forces are comparatively stronger than other forces.
In nuclear reactions, the "light" which must be radiated to remove binding energy may be in the form of direct gamma radiation. Again, however, no mass-deficit can in theory appear until this radiation has been emitted and is no longer part of the system.
The energy given off during either nuclear fusion or nuclear fission is the difference between the binding energies of the fuel and the fusion or fission products. In practice, this energy may also be calculated from the substantial mass differences between the fuel and products, once evolved heat and radiation have been removed.
--Until our energy infrastructure is based on matter-antimatter reactions, don't you think we can safely ignore mass-energy equivalence considerations?--
Do you want us to shutdown our nuclear power plants? That would put me out of a job.
--Your links and explanation (which is just copied from the link, I have been reading them) still is referring to nuclear reactions. The combustion of ethanol is not an atomic reaction.--
They apply to all. From my 91:
Closely analogous considerations apply in chemical and nuclear considerations. However, in nuclear reactions, the fraction of mass which may be removed as light or heat, and which then appears as binding energy, is often a much larger fraction of the system mass. This is because nuclear forces are comparatively stronger than other forces.
--Matter is not transformed to heat or light in this reaction.--
You've convinced me. Einstein was wrong. Discussion is over.
The probllem with your demand that ethanol by products be used to fuel the ethanol still is that those by-products are edible and have a much higher value as high protein animal feeds. Sure, DDG's will burn (and in so doing produce more heat than is needed to drive the still), but at current market values the DDG's are worth much more as animal feed.
Ooops. That wasn't your demand, was it.
This isn't something I need to discuss with my cows, is it?
In fact Einstein's relationship tells us more, it says Energy and mass are interchangeable. Or, better said, rest mass is just one form of energy. For a compound object, the mass of the composite is not just the sum of the masses of the constituents but the sum of their energies, including kinetic, potential, and mass energy. The equation E=mc2 shows how to convert between energy units and mass units. Even a small mass corresponds to a significant amount of energy.
In the case of an atomic explosion, mass energy is released as kinetic energy of the resulting material, which has slightly less mass than the original material. In any particle decay process, some of the initial mass energy becomes kinetic energy of the products. Even in chemical processes there are tiny changes in mass which correspond to the energy released or absorbed in a process. When chemists talk about conservation of mass, they mean that the sum of the masses of the atoms involved does not change. However, the masses of molecules are slightly smaller than the sum of the masses of the atoms they contain (which is why molecules do not just fall apart into atoms). If we look at the actual molecular masses, we find tiny mass changes do occur in any chemical reaction.
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