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Assume that the initial temperature is room temperature and neglect the initial amount of acetonitrile in the gas phase. Calculate the equilibrium vapor pressure of acetonitrile at 140 C and compare it with the partial pressure you would calculate from the ideal gas law if all the acetonitrile had evaporated (so that its volume is 100 cc). If the latter is ...


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You notion (1) is just wrong. With notion (2) You have the right idea. You'd need to make some assumptions to solve the problem. So state your assumption and solve the problem from there. I had a wonderful high school teacher who was a stickler for answers to include any assumptions. At the time it was painful, but in retrospect it was wonderful ...


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First, not all gases can be liquefied at room temperature by increasing pressure. If the gas is above the critical temperature, it cannot be liquefied by any increase in pressure; it becomes a supercritical fluid. Supercritical fluids have some of the properties of a gas (e.g. diffusing through fine openings), ans some of liquids (e.g. dissolving solids and ...


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As one increases the pressure, the volume occupied by the gas decreases. Like you said, the temperature should increase with increasing pressure. Equivalently you could say that the thermal energy of the molecules of the gas has increased which manifests itself in increased collisions and vibrations of the constituent molecules. The decrement in volume ...


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Many low pressure gases glow when undergoing an electrical discharge Plasma globes are simple vessels containing low pressure gas mixtures (often noble gases). They are usually driven by something like a Tesla Coil (or by an electronic circuit that produces the same high voltage high frequency output as a tesla coil). Neon signs and standard fluorescent ...


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In the ideal gas, $3R/2$ is the thermodynamic entropy of one Mol. The factor $\frac{3}{2}$ comes from $ST=N\bar{E}=N\frac{3k}{2}T=\frac{3R}{2}T$. The energy of 1 Mol of ideal gas is either given by $3pV/2$ or $3RT/2$ or $ST$. (In the ideal gas) the entropy does not depend on temperature. That is why one writes the $T$ separate in $TS$. For non-ideal gases ...


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As already noted by Maurice, yes you did liquify a gas under pressure. In fact, the scope of application is so wide that this is equally known as Linde cycle. It is highly possible that you have such an engine at home, either as fridge, or freezer to cool stuff, or as heat pump to warm a home. Regarding propane: equally yes. After banning Freon and other ...


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In terms of macroscopic thermodynamics (no molecular-based arguments are necessary), the underlying reason for distinguishing between an "ideal gas" and a "perfect gas" is that a mixture (solution) of gases may be an "ideal solution", but each of its components need not be an ideal gas. In the case of a single component gas phase, it is more precise to ...


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The compression by the blower can be used as an example of adiabatic compression. $$pV^\gamma=\text{constant}$$ or $$p_1V_1^\gamma=p_2V_2^\gamma$$ where $\gamma$ is the ratio of the heat capacities $\gamma=C_p/C_V=C_{\mathrm m,p}/C_{\mathrm m,V}=c_p/c_V$. You need to find a value of $\gamma$ suitable for your biogas, which is probably mainly a mixture of $\...


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