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A supercritical fluid is just a state of matter. like solid, liquid or gas. Hexane is no more or less toxic if it has become supercritical and then brought back to standard temperature and pressure, as would water, if it changed from liquid to ice or to supercritical "steam" and back to water. Further, supercritical $\ce{CO2}$ is used for dry-...


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Jon Custer helpfully noted (in a comment) two common production processes that result in compression of the final product. I did some research to discover the typical pressures involved. Tempered Glass Glass may be tempered by cooling the outer layer quickly, while letting the inner layer cool slowly. As the inner layer cools, it shrinks; but because the ...


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Why wouldn't the net work done on the gas be equal to the work done on both the gas and the atmosphere, which is also applying a force on the gas? Your phrasing is not quite correct: The work done on the gas in the cylinder is equal to the work done by the atmosphere (if any), plus the work done by the lowering of the weights (if any). I.e., the gas is ...


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The total work ( and its value for the constant force case ) for pressure $$p=p_\mathrm{force} + p_\mathrm{atm}$$ $$W_\mathrm{tot} = - \int_{V1}^{V2}{p \cdot \mathrm{d}V} $$ is shared between the source of the explicit mechanical force acting on piston and atmosphere. Atmosphere would do work $$W_\mathrm{atm} = - \int_{V1}^{V2}{p_\mathrm{atm} \cdot \...


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You have differential equations. Differential equations are ALL about the initial conditions, and A PROCESS. So, what’s the initial condition? You have a piston with a given volume of gas. What’s happening then? I apply an additional force with an object. (The atmospheric pressure already was there) And what if you want to know the work made by the ...


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Partial pressure is defined as the pressure a component of a gaseous mixture would exert if it alone were to occupy the container at the same temperature as that of the mixture. If the gases in the mixture are ideal, you can apply the ideal gas equation for it $$p_A V = n_ART$$where $p_A$ and $n_A$ represents the partial pressure and number of moles of a ...


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When we cook something inside a pressure cooker, we are able to manipulate the pressure inside of the pressure cooker. This is useful, because we know that changes in pressure can cause changes in boiling point. Let me explain. Boiling Point In Terms of Pressure A chemists definition of boiling point is the point at which the vapor pressure of the liquid ...


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According to their website, the manufacturers say "The Ultra and Max models of Instant Pot come with the ability to adjust pressure settings to account for altitude." So, yes, the timings will be affected by altitude, even in a pressure cooker. This is probably because the pressure inside the cooker is controlled by some method that uses the ...


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When water evaporates the hotter molecules leave and they take some heat with them. Which cools down what's left in the pot. You keep heating your pot and more molecules evaporate, which in turn cools down the pot more. When you just started to heat water - the amount of heat absorbed by the water is greater than the cooling effect of evaporation and the ...


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An ideal pressure cooker is an isolated vessel in which what goes on inside is independent of what happens outside. It allows the temperature of what you put in the cooker to be raised until the vapor pressure reaches a set point (a pressure higher than the pressure at the standard boiling point of water). Since cooking time depends only on the temperature ...


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