Questions tagged [equation-of-state]

Questions related to a thermodynamic equation describing the state of matter under a given set of physical conditions.

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Why are equations of state for a non-ideal gas so elusive?

The ideal gas equation (daresay "law") is a fascinating combination of the work of dozens of scientists over a long period of time. I encountered Van der Waals interpretation for non-ideal gases ...
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What is a rigorous definition of gas volume, and how is the Van der Waals equation derived?

I am confused about the justification for the corrections to the ideal gas law in the Van der Waals equation: $$p=\frac{nRT}{V-nb}-a\left(\frac{n}{V}\right)^2$$ I understand that the equation ...
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Why is the van der Waals coefficient b equal to four times the volume of the particle?

In the van der Waals equation of state $$\left[p + a\left(\frac{n}{V}\right)^2\right](V-nb) = nRT$$ the coefficient $b$ is supposed to represent the volume occupied by the particles. Why then is it ...
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Ideal gas equation derivation proportionality [duplicate]

While deriving the Ideal gas Equation using Boyle's, Charles', and Avogadro Laws, how are each of the laws, which have different proportionality constants and different quantities as constant combined?...
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Why is the pressure correction added in the Van der Waals equation?

Since real gas particles experience attraction to each other, that means the pressure must be less from what we would expect. So why do we have to add a term to correct it? For example, in the ...
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What is the chemical equation, along with the change in heat of the crystallization process of Sodium Acetate

This is the reaction found in chemical hand warmers, and I can't figure out the equation and the change in heat. Any help would be greatly appreciated
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At what pressure is the triple point of ethane?

Depending on source there are two givens for the triple point of ethane: 0.8 Pa or 1.1 Pa. Only one of them can be correct, which one is?
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How to determine if pressure surpasses capacity with the van der Waals equation of state?

I have to decide whether a $\pu{20 L}$ container with $\pu{0.8 kg}$ ethane can withstand the pressure at $\pu{373.15 K}$. The following information is given: \begin{align} b &= \pu{6.448x10^-2 ...
I have found it mentioned in various sources that the value of R depends on the amount of substance $n$ in the ideal gas equation: $PV=nRT$ If this is true, it would imply that $R$ is a function of $n$...