Maximizing Expansion: Understanding Heat's Impact on Gas Expansion Rates

  • Context: Undergrad 
  • Thread starter Thread starter mtanti
  • Start date Start date
  • Tags Tags
    Expansion
Click For Summary

Discussion Overview

The discussion centers on how gases expand in response to heat, specifically whether different gases exhibit varying expansion rates with the same increase in temperature. Participants explore the relationship between heat capacity and gas expansion, as well as the factors influencing these properties.

Discussion Character

  • Exploratory, Technical explanation, Conceptual clarification

Main Points Raised

  • One participant questions whether gases expand differently with the same increase in heat and seeks to identify which gas expands the most and by what amount.
  • Another participant suggests reviewing the Gas Law for relevant information.
  • A participant presents a formula relating the relative increase in volume to temperature change and heat, indicating that the expansion is influenced by heat capacity.
  • It is noted that the heat capacity of a gas, which affects its expansion, depends on the degrees of freedom of the gas molecules, with diatomic gases having higher heat capacities than monatomic gases. This relationship is linked to the molecular structure and mass of the gas molecules.

Areas of Agreement / Disagreement

Participants express varying viewpoints on the factors influencing gas expansion, particularly regarding the role of heat capacity and molecular structure. No consensus is reached on the specific expansion rates of different gases.

Contextual Notes

The discussion does not resolve the specific mathematical relationships or assumptions regarding the heat capacities of different gases, nor does it clarify the exact conditions under which the expansion is measured.

mtanti
Messages
172
Reaction score
0
I'de like to know if gases expand differently with the same amount of increase in heat. If so which is the one which expands most and by how much?
10x!
 
Last edited:
Physics news on Phys.org
You may want to read up on the Gas Law...
 
In particular, the relative increase in volume

[tex]\frac {\Delta V}{V_0} = \frac{\Delta T}{T_0} \approx \frac {Q}{C_p T_0}~~\alpha ~~\frac{1}{C_p}[/tex] for a given amt of heat.
 
As Gokul indicated it depends in Cp, the heat capacity of the gas. The heat capacity depends on the degrees of freedom of the gas molecule. This in turns depends on the complexity of the structure of the gas. Diatomic gases for instance, have higher heat capacities than monatomic gases. Heat capacity also increase with the mass of the molecules. This is due to the fact that temperature at the molecular level is really vibrational and rotational energies of the molecules, which increases with the increasing moment of inertia of the molecules.
 

Similar threads

  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 24 ·
Replies
24
Views
2K
Replies
2
Views
2K
  • · Replies 9 ·
Replies
9
Views
4K
  • · Replies 6 ·
Replies
6
Views
2K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 67 ·
3
Replies
67
Views
6K
  • · Replies 7 ·
Replies
7
Views
4K