Proof gas loses 1/273 of its volume - Charle's Law

Click For Summary

Discussion Overview

The discussion revolves around demonstrating that a gas loses 1/273 of its volume when cooled by 1 Celsius degree, in accordance with Charles's Law. The focus is on the mathematical derivation and understanding of the relationship between volume and temperature for gases, particularly at the freezing point of water.

Discussion Character

  • Homework-related
  • Mathematical reasoning
  • Conceptual clarification

Main Points Raised

  • The initial post presents a mathematical approach using Charles's Law to relate the initial and final volumes of a gas as temperature changes.
  • The author attempts to derive the final volume, V2, from the initial volume, V1, and expresses the relationship as V2 = (272/273)V1.
  • One participant suggests that the statement about losing 1/273 of the volume does not imply that V2 equals 1/273, and recommends expressing the loss in terms of V1 - V2 or V2/V1.
  • Another participant notes that volume is proportional to temperature in Kelvin and discusses the theoretical volume at absolute zero (0K), emphasizing that this only applies to ideal gases.
  • There is a mention that the discussion about gas behavior at 0K is off-topic for the original question posed by the author.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the relevance of discussing gas behavior at absolute zero, and there are differing views on how to express the volume loss in relation to the initial volume.

Contextual Notes

The discussion includes assumptions about ideal gas behavior and the implications of temperature changes on volume, which may not hold in all scenarios.

ghostanime2001
Messages
256
Reaction score
0

Homework Statement


Show that any gas loses 1/273 of its volume at 0 °C, when it is cooled by 1 Celsius degree.

V_{1}=?

V_{2}=?

T_{1}=0 °C=273 K

T_{2}=272 K

Homework Equations


I'm assuming I have to use Charle's Law AND starting with any starting arbitrary volume:

\dfrac{V_{1}}{T_{1}}=\dfrac{V_{2}}{T_{2}}

The Attempt at a Solution



So substituting in all the values above and solving for V2 I get:

\dfrac{V_{1}}{273}=\dfrac{V_{2}}{272}

272V_{1}=273V_{2}

\dfrac{272}{273}V_{1}=V_{2}

\dfrac{273-1}{273}V_{1}=V_{2}

\left(\dfrac{273}{273}-\dfrac{1}{273}\right)V_{1}=V_{2}

\left(1-\dfrac{1}{273}\right)V_{1}=V_{2}

V_{1}-\dfrac{1}{273}V_{1}=V_{2}

That's as far as I can get and I guess it makes sense? If I start with any V_{1} i subtract that with 1/273th of the initial volume and i get the second volume. Assuming I start with

V_{1}=1 L, the second volume V_{2} would be 0.996 L. The second set of experimental conditions are colder so I expect the volume to decrease following Charle's Law.

BUT! am I supposed to show explicitly that \dfrac{1}{273}=V_{2} ? How do I show \dfrac{1}{273}=V_{2} explicitly?
 
Physics news on Phys.org
You are almost done. Hint: loses 1/273 volume doesn't mean V2=1/273. Try to express the loss in terms of V1-V2, or V2/V1.
 
Volume is proportional to T in Kelvins.
The volume at 0C (273K) = Vo, the volume at -273C (0K) = 0
Change in volume ? Change in temp ?
 
technician said:
the volume at -273C (0K) = 0
Change in volume ? Change in temp ?
The volume at 0K = 0 only holds for ideal gases (hint: nothing is ideal).
 
removed
 
Last edited:
This discussion if off topic, and in no way helpful for the OP. Question doesn't need any information about gas behavior at 0 deg K to be solved.
 

Similar threads

Replies
49
Views
3K
Replies
1
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 11 ·
Replies
11
Views
1K
  • · Replies 8 ·
Replies
8
Views
4K
  • · Replies 7 ·
Replies
7
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 8 ·
Replies
8
Views
3K
Replies
17
Views
3K