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Regarding the first question, I believe that you missed a couple of sentences in the Efficiency section of the Wikipedia article: It also requires energy to overcome the change in entropy of the reaction. Therefore, the process cannot proceed below 286 kJ per mol if no external heat/energy is added. If you use 286 kJ/mol, you "don't get something for ...


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I've seen this question some years ago. Note that the water level doesn't change as the ice melts ONLY if the ice is melting in pure water. If you melt ice cubes in salt water, the water level will increase as the ice melts.


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The displacement answers of mew and kal are spot on. This is about the chemistry of the displacement. Water is the only substance with solid density less than the liquid. As you cool a liquid and it settles in and get more dense. As it settles to solid it typically just settles in more. Water is very a interesting molecule in that it is very stable ...


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Yes the core will warm gradually. Heat transfer in a solid is conduction. Ice has a known thermal conductivity and will have a linear temperature profile from all paths from surface to center. There will be concentric rings of constant temperature at all times. It would be impossible to warm just the surface and not warm up the molecules next to the ...


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In fact, the water would act as a neutron moderator, speeding up the reaction. However, reactor pressure vessels are quite sturdy, and it would be very unlikely for the salt water to enter the pressure vessel.


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If you are above the water you will get accelerated down until the weight of the water you disperse is equal to your own weight (calling this level $x$). As soon as you are completely submerged the gravitational force downwards will be $\rho Vg$ and by Archimedes principle the force upwards will be $\rho_w V g$, where $\rho$ is your density, $V$ is your ...


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What is important in the idea of resonance with water is to establish a frequency of excitation that causes the natural frequencies to superimpose or wave superposition. By achieving wave superposition the amplitude of the oscillations will have the greatest potential of breaking the molecule into its elemental constituents thereby creating free atoms that ...


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When the pressure increases, the flow decreases thereby providing the same "power". You can have larger flow if you naturally decrease the pressure, or larger pressure if you restrict the flow.


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I'm appreciating your thinking and question. This question will be even more challenging question if the working fluid is air instead of water and fluid is moving. In this answer I'm considering bottle is moving and fluid is moving in opposite direction of bottle. (because stationary fluid is sub case of moving fluid where $v_1$=0) Let us assume the the ...


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The opening sees water at stagnation pressure. Water will flow in until the air in the bottle is squeezed to that pressure.


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I looked up some of the original publications by Harmon Craig. There are a ton of them, and they are very highly cited. For example, in Isotopic exchange effects in the evaporation of water: 1. Low-temperature experimental results (Journal of Geophysical Research, 1963 - DOI 10.1029/JZ068i017p05079) the abstract states: The deuterium and oxygen 18 ...


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The water in the Oceans is partly 1) the original water from their formation and this will have come into equilibrium with the underlying strata of earth. These strongly depend on location for the chemicals composing them and this will apply to the isotopes in these chemicals 2) Rain water which brings down whatever dust exists in the atmosphere, and ...


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I guess the isotopic composition of seawater depends on temperature, among other things, as water comprising lighter isotopes evaporates more easily.


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The evaportation rate is given by $${dM \over dt} \sim T$$ where $M$ is the amount of evaporated water and $t$ is the time. $T$ is the temperature of the water. However, $${dM \over dt} \sim Q$$ Where Q is the charge of the water, to prove my point, consider a lightning bolt impacting water. The water is split into hydrogen and oxygen through electrolysis. ...


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In fact ice is slightly less reflective than water. The reflectivity is related to the refractive index (in a rather complicated way) and the refractive index of ice is 1.31 while the refractive index of water is 1.33. The slightly lower refractive index of ice will cause a slightly lower reflectivity. In both cases the reflectivity is about 0.05 i.e. at an ...


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There are lots of tried and tested methods for visualising flows, for example mica or aluminium flakes though these tend to settle fairly quickly. In days gone by I used zirconium phosphate that had been delaminated by titrating with tetramethyl ammonia. This gives very thin flakes that are stable to sedimentation for a day or so, though you have to prepare ...


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According to "Surface chemistry of gold nanoparticles produced by laser ablation in aqueous media." Sylvestre J-P, Poulin S, Kabashin AV, Sacher E, Meunier M, Luong JHT http://pubs.acs.org/doi/pdf/10.1021/jp047134%2B A detailed chemical analysis showed that the nanoparticles formed were partially oxidized by the oxygen present in solution. The ...


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Lots of poor info here. Ribs are not an impenetrable barrier, compression happens between them. Fat can also be compressed so is not bouyant. Equalization of bouyancy for humans happens at approx 4m below the surface. So jumping off a medium height bridge into water 'just to cool off' means you won't get to the surface unless you swim upwards.


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If you place water (or other material) in a pressure-tight container, the water will change as heat and pressure cause its molecules to become more or less energetic and the bonds among its molecules to become more or less stable, or begin breaking apart. These changes are summarized in a chart called a phase diagram. Here is a simple phase diagram for ...


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EDIT#2: I'm now made aware that you need wavelengths that are much larger than those presented here(a bit of an oops from reading this question quickly). This approach is still valid, but what you need cannot be obtained from these data. I'm going to leave this here however to collect downvotes and if anyone needs $\epsilon_r$ as it depends on $10^{7}$ to ...



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