Can you sort molecules by speed based on temperature?

Click For Summary

Discussion Overview

The discussion centers around the relationship between temperature and molecular speed, specifically whether it is theoretically possible to sort molecules by their speed to create water at different temperatures from a single source. The scope includes conceptual understanding and theoretical implications.

Discussion Character

  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant suggests that temperature is proportional to the speed of molecules and questions if sorting molecules by speed could yield water at a higher temperature from a lower temperature source.
  • Another participant challenges the initial question by emphasizing the need to consider how one would separate faster molecules from slower ones.
  • A later reply indicates that the question is more complex than it appears and references Maxwell's Demon as a relevant concept, suggesting that the answer is not straightforward.
  • Some participants express frustration over perceived dismissiveness and emphasize the importance of addressing the original question regarding sorting molecules.

Areas of Agreement / Disagreement

Participants do not reach a consensus. There are competing views on the feasibility of sorting molecules by speed and the implications of temperature on molecular motion.

Contextual Notes

The discussion highlights limitations in understanding the practicalities of sorting molecules and the theoretical implications of temperature and molecular speed, without resolving these complexities.

colin9876
Messages
23
Reaction score
0
Can someone explain if my understanding is correct- that temperature of say a liquid is proportional to the speed of the molecules?

My idea is if there was a way to sort different molecules by speed, could you say in theory, take 1litre of water at 30degrees and pick out the fastest molecules and say have 50mls of water at 50degrees C leaving the remainder 950mls at 28 degrees centigrate etc?
 
Science news on Phys.org
Excuse me ? No one asked to contribute to my question, so that sort of attidude not required thanks. The post you reference does not answer the point about 'sorting out' the fasted moving molecules.

My question is if there was some way to sort molecules could you get some hotter water out of some colder water - in theory
 
why the hell are you going off at me for? remember this question:
colin9876 said:
Can someone explain if my understanding is correct- that temperature of say a liquid is proportional to the speed of the molecules?

that link I gave you answered that question. Not to mention, all I said was search your questions before asking - it's a sticky thread if you havn't noticed.

to your molecule question: If there was a way to sort out molecules; the question would then be how do you separate the hotter molecules from the colder ones?

rough estimates or exactly?
 
colin9876 said:
Can someone explain if my understanding is correct- that temperature of say a liquid is proportional to the speed of the molecules?

My idea is if there was a way to sort different molecules by speed, could you say in theory, take 1litre of water at 30degrees and pick out the fastest molecules and say have 50mls of water at 50degrees C leaving the remainder 950mls at 28 degrees centigrate etc?
It's a tricky question, with an answer that is more subtle than one might think. The short answer is: no, it won't work. As to why, you'll have to do some more reading, as this the answer is more involved than a forum will really allow.

Read up on Maxwell's Demon - it deals directly and exactly with what you are asking.
 

Similar threads

Undergrad Temperature and the kinetic energy of everything
  • · Replies 5 ·
Replies
5
Views
21K
High School Simple liquid/gas law question and liquid transfer query
  • · Replies 9 ·
Replies
9
Views
2K
Undergrad Why Does Hot Water Freeze Faster Than Cold?
  • · Replies 10 ·
Replies
10
Views
3K
Undergrad How to measure the temperature of liquid in sealed container
  • · Replies 3 ·
Replies
3
Views
3K
High School Can Molecules Have Defined Position and Momentum Before Measurement?
  • · Replies 17 ·
Replies
17
Views
2K
Can blowing on liquids actually cool them down?
  • · Replies 4 ·
Replies
4
Views
3K
Undergrad Can you have a high temperature with very little heat?
  • · Replies 3 ·
Replies
3
Views
1K
High School How can I model a density function of a compressible fluid?
  • · Replies 2 ·
Replies
2
Views
2K
High School How does sweating cool a person down?
  • · Replies 9 ·
Replies
9
Views
15K
How do you determine the pKa values of novel bases?
  • · Replies 1 ·
Replies
1
Views
3K