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The answer is, it depends on the type of fireplace you have. An ordinary brick chimney consisting of a fireplace directly venting up and to the outside has a very low efficiency. The draft generated by the fire pulls warm air from the house, and most of the heat travels directly up. There are various types of fireplaces which specifically attempt to ...


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HSAB is an empirical classification of chemical species on the basis of mutual reactivity or inertness towards each other - it is not a theory in the sense of fundamental framework. Klopman-Salem equation is post facto rationalisation in terms of one-electron wavefunctions, the results of which are inherently dependent on chosen atomic basis, and/or any post ...


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This is an excellent question, but not readily answered, as discussed in Floris's Answer. Here is a stab at how to get an estimate of efficiency. It is the method which I believe is reasonably accurate: the actual values will need to be refined by experimental measurement: I am not too confident of the actual numbers that fall out owing to the ...


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This is such a complicated question! The worst part is that as heat leaves the chimney, it draws air from the room with it - air that needs to be replaced from outside. This actually makes fires quite good as ventilation systems. Whether a fire heats a building depends in very large part on the degree to which cool air can flow past parts heated by the ...


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Although they are quite fundamental quantum mechanically (they are the propagation equations for the free photon), Maxwell's equations alone are severely limited. They only describe free photons, or with the appropriate constitutive relationships, they can describe the propagation of a quantum superposition of free photons and raised matter states in ...


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You have assumed that Koopman's theorem is correct. I am afraid that Koopman's theorem is a good first approximation but does not take account of the following issue. When an atom or molecule is ionized then by Koopman's theorem the energy required is equal to the energy of the orbital the electron is in. What this neglects is that by removing an electron ...


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A couple of points. outermost occupied subshell generally everything that is in the outershell n highest (and sometimes electrons from lower subshells e.g. 3d in first row of transitions metals) has an impact on the chemistry and we can't generally say it is just the outer subshell. noble gases in general chemical discussion 8 electrons is ...


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This has everything to do with entropy: when the temperature is higher, the benefit of having more water molecules in the air (giving rise to greater entropy) become energetically more favored. This is why water "dissolves better in air" at higher temperatures. Another way of looking at this (pure statistical thermodynamics): when water is cold, few ...


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This phenomenon has nothing to do with the properties of the air, but the properties of the water in it. Hot air means hot water in the air. Cold air means cold water in the air. Cooling water causes it to condense. This is considering a constant volume.


-4

ice is a crystal pure made up of water after frozen on a certain temperature,as it is lighter than water hence its density is less than water............this can be taken as in simple words


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This may be obvious to Fermi, but not to the rest of us. One has to keep in mind the context of the derivation, Fermi is talking here about ideal gases. In other words, gases which are very dilute, such that the interparticle distance is much much larger than the range of the interparticle interaction. This means that particles don't see each other ...



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