Understanding the Gas Constant: A Key Concept in Thermodynamics

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Discussion Overview

The discussion centers around the concept of the gas constant, R, in thermodynamics, exploring its definition, significance, and implications in gas behavior under various conditions. Participants examine both theoretical and experimental perspectives related to R's role in equations involving pressure, volume, and temperature.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant expresses confusion about the meaning of the gas constant, R, and seeks clarification on its definition.
  • Another participant suggests that R has no intrinsic meaning beyond being a scaling factor necessary for calculations involving temperature, pressure, and volume.
  • A participant describes an experimental observation that at low pressure, the product of pressure and volume (PV) is proportional to temperature (T), noting that R has a consistent value for one mole of gas across different types of gases.
  • A later reply reiterates the previous point about R being a universal molar gas constant, suggesting it can be viewed as an experimental coefficient relating PV to T from a molar mass perspective.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the meaning of R, with differing views on its significance and interpretation. Some emphasize its role as a scaling factor, while others focus on its experimental implications.

Contextual Notes

The discussion reflects varying interpretations of the gas constant, highlighting potential ambiguities in its definition and application. There are also repeated claims that may indicate a lack of clarity or consensus on the underlying principles.

Su Solberg
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I wonder what's the meaning of Gas constant, R.
I have read it in Wikipedia, but i still cannot understand.
Could you please tell me some concept about R's definition?

Thank you very much for your information.
 
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There's no great meaning behind it. We have an arbitrary set of units as far as the universe is concerned, so when we try to do things like calculate temperature based on pressure and volume, we need to take this into account by scaling by a certain amount.
 
Experiment shows that for a gas at low pressure PV is proportional to T ,therefore PV= a constant times T.If 1Kg of gas is considered then the constant has different values for different gases but if 1 mole is considered then the constant,R,has the same value for all gases(hence the name...universal molar gas constant)
 
Dadface said:
Experiment shows that for a gas at low pressure PV is proportional to T ,therefore PV= a constant times T.If 1Kg of gas is considered then the constant has different values for different gases but if 1 mole is considered then the constant,R,has the same value for all gases(hence the name...universal molar gas constant)

I think you answered my question.
Can I read it as R is an experimental coefficient about the gas/vapour/other stuff which relates to the interaction of PV with T from Molar Mass point of view>?
 

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