Solving the ideal gas law for volume -> length

Click For Summary
The discussion revolves around calculating the edge length of a cube surrounding each molecule of an ideal gas at 27.0 degrees Celsius and 1.00 atmosphere pressure. Using the ideal gas law, the volume for one mole of gas is determined to be 2.46 x 10^-2 m^3, leading to a volume per molecule of approximately 4.09 x 10^-26 m^3. The user questions why their calculated edge length of 0.000000003 m differs from the expected value of 3.44 x 10^-9 m. The correct approach involves taking the cube root of the volume per molecule, which yields the accurate edge length. Clarification on the calculation process is suggested, along with the recommendation to consult a teacher for further guidance.
jaded18
Messages
149
Reaction score
0
[SOLVED] solving the ideal gas law for volume --> length

Consider an ideal gas at 27.0 degrees Celsius and 1.00 atmosphere pressure. Imagine the molecules to be uniformly spaced, with each molecule at the center of a small cube.

What is the length L of an edge of each small cube if adjacent cubes touch but don't overlap?
______________

I know that the ideal gas law states V=nRT/p and that in this case R=8.2057(10^-5) m^3 (atm/mol*K), p=1atm, T=27+273K. What is n? Well if I calculate the volume of one mole of the gas, I get V=2.46(10^-2) m^3. And then when I use this result to find the volume of one molecule (the volume of the imaginary cube that is assumed to surround each molecule, I get V=( 1/(6.02*10^23))(8.2057)(27+273)= 4.09*10^-26 m^3

Then don't I just use this volume per molecule that I just calculated to find the length of a side of the cube by taking the cube root of it?! Why isn't the answer 0.000000003m?!

No one at the physics forum could help, so if you know how to do this prob correctly, any feedback will be awesome
 
Physics news on Phys.org
I think you've done it properly. You get 3.44 x 10^-9 m. That's the right magnitude anyway. Maybe ask your teacher?
 

Similar threads

Replies
9
Views
2K
Replies
1
Views
2K
  • · Replies 16 ·
Replies
16
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 6 ·
Replies
6
Views
3K
Replies
24
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 4 ·
Replies
4
Views
7K
  • · Replies 35 ·
2
Replies
35
Views
5K