# Tag Info

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Increasing thermal efficiency in cooking pasta I'll assume you mean 'use less energy to obtain the goal of properly cooked pasta'. There's a variety of things you can do. Boil less vigorously. A 'rolling boil' is generally advertised for cooking pasta but boiling less intensely will save quite some energy. Use less water. The amount of energy needed to ...

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Yes and no. It is indeed true that for every emission line, there is a corresponding absorption transition that, under suitable conditions, can be observed in an absorption spectrum. However, it is not true that if you take an emission spectrum and an absorption spectrum from the same atom, the lines in the two must always match. The reason is simply that ...

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if you fired a gun in a room containing nothing but hydrogen, nothing would happen. for hydrogen to explode it first needs to be mixed with a certain amount of oxygen.

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One can certainly separate water molecules at low temperature on a surface, as demonstrated by STM images. In Hossain et al. 2003 they show that the molecules stick to C defects on the surface. In (Shin et al 2010) they have nicer pictures of dissociated molecules on the surface. I suspect one can also make free-flying vacuum molecules simply by having ...

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I'll try to provide an answer which, in addition to provide information for the original poster could help those thinking that this question should be closed that beyond the practical problem there is some genuine theoretical and experimental physics. Dried pasta is made by flour, salt and water. For some special pastas also eggs are added. After mixing ...

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Not in general (though it is very common). Under some conditions you can have states that are reached by a single absorption event (creating a high energy absorption line) that decay (with a non-trivial branching ratio) through several steps (creating several lower energy emission lines). Indeed this kind of process is the usual scheme for setting a ...

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Yes, mostly. The Coulomb force is described by but one of the four Maxwell Equations, acting between the (mostly) stationary protons and neutrons in the nucleus and the fast-moving electrons that can be found, each in its orbital, though protons, neutrons, and electrons all also have magnetic moments. Coulomb's Law is the only one of the equations that is ...

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The potential term in the Hamiltonian is based only on the Coulomb interaction. They are the causes of chemical bonds.

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To amplify the answer by @nielsnielsen I'll start by repeating that hydrogen by itself is not flammable. In order for it to burn you need at least some oxygen. The resulting chemical reaction forms $H_2O$ (water). In addition, for hydrogen to burn the percentage of hydrogen to oxygen has to be between 4% and 95%. If you use air instead of oxygen, then the ...

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