Does doubling temperature double average molecular speed?

  • Thread starter Thread starter Dx
  • Start date Start date
  • Tags Tags
    Kinetic
Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
2 replies · 3K views
Dx
[SOLVED] temp and kinetic th

Hiya!
Just 2 quick questions that i may ask which will help me solve for my problems i am working on.

1) In order to double the avg speed of molecules in a simple gas, the temp(in K) must be double also right?

2) And if a ideal gas is compressed slowly to 1/2 its origianl volume with no temp change then the avg speed also is 1/2.

i can't find where i read that at but working on these two problems i have i want to make sure that these 2 questions i am asking you guys are right so i can answer my two prblems i am working on.

Thanks!
Dx :wink:
 
Physics news on Phys.org
Heres the equation for average velocity of ideal gas molecules... U can take it from there

Vrms=[squ]3RT/M where M is molecular mass and R is 8.31


For the second one, if there is no temperature change, then there is no change in avg velocity since it is only dependent on temperature and the problem states that temperature is held constant
 


Hi Dx,

You are correct in both of your assumptions. According to the kinetic theory of gases, the average speed of gas molecules is directly proportional to the temperature in Kelvin. This means that when the temperature is doubled, the average speed of the molecules will also double. This is because an increase in temperature causes an increase in the kinetic energy of the molecules, which in turn increases their speed.

In the second scenario, when an ideal gas is compressed slowly with no change in temperature, the average speed of the molecules will decrease by half. This is because the volume of the gas is decreased, which means that the molecules will have less space to move around and their average speed will decrease accordingly.

I hope this helps you in solving your problems. Good luck! :)