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These two refrigerants have different boiling points and thus different pressure requirements in the system. Refrigerants are not interchangeable, apart from a very few, I think R134a could be put in old R12 auto systems with a relatively small loss of efficiency. Look up the characteristics of each refrigerant to answer the question. I don't know what ...


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This is my opinion (as an engineer) as to why the modulus of Elasticity --as it is used by engineers-- cannot be applied in the same manner in this context (at least without significant modification). Modulus of Elasticity common engineering definition The usual definition of the Young's Modulus is: $$E = \frac{\Delta \sigma}{\Delta \epsilon}$$ where: $\...


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Hydrogen will not liquify no matter how high it is compressed. Unless it is cooled down to its critical temperature which is $ - 252.8^{\circ}C$ Hydrogen can be physically stored as either a gas or a liquid. Storage as a gas typically requires high-pressure tanks (5000–10,000 psi tank pressure). Storage of hydrogen as a liquid requires cryogenic ...


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You need to find the compressibility factor, which is defined as $Z = \dfrac{pV}{nRT}$ of the hydrogen, then correlate to the "ideal gas", which has a compressibility factor of 1. https://en.wikipedia.org/wiki/Compressibility_factor


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If you have opportunity, just measure it. Resulting chart curve's equation can be estimated by a regression equation. Differentiate it for a given time and find the instantaneous rate.


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If the lower grade pipe is not rated for that pressure, it'll bust. The solution is to transfer the water to a water reservoir/tank in a lower elevation, which acts to relieve the excessive pressure by reducing the head. But you might have to adjust the pipe size to maintain the flow rate.


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They heat the jars and take them out of the oven open the lid to let the pressure out and then close it. Once the jar gets cooler the pressure inside that was occupied with hot expanded air settles and the air volume shrinks back causing it to create a small vacuum. Many times early in the chill mornings I see my bottle of water left in the cup holder ...


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What they are doing in the video is heating up the liquid inside the vessel, (with an open lid). Then they take it out and immediately (i.e. before it cools down), they pack the lid. What happens is that as the liquid cools down, and the temperature (in Kelvin) drops then the pressure drops. An approximation is the ideal gas law (although as Abel pointed in ...


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Not checked out the video, but if you put a jar with a liftable lid in a vacuum sealer then as the pressure outside the jar is reduced air in the jar will push past the seal to equalize the pressure. Once the sealer is opened then as long as the jar seal is good the reduced pressure will stay in the jar.


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