Ideal gas question(thermal physics)

In summary, the task is to estimate the number of air molecules in an average sized room. One possible equation to use is N=n*N(a), where N(a) is Avogadro's number and n is the number of molecules. Another approach is to use the Ideal Gas Equation, PV=RTn, to calculate n and then multiply it by N(a). In order to use this equation, the values for P, V, and T must be known. Assuming the room is a cube with a length of 25 meters, the volume can be calculated by cubing the length of the side. However, the original values given for temperature and pressure are in the wrong units and the room size is likely much larger than the average room
  • #1
Benzoate
422
0

Homework Statement



estimate the number of air molecules in an average sized room

Homework Equations



possible equation: N=n*N(a) , N(a) being avogradro number. N being the number of molecules. PV=RTn

The Attempt at a Solution



So should I guesstimate what n should be and the multiply that by avogradro number to get my total number of molecules. Or maybe I should apply the Ideal gas equation to find n and then multiply n by N(a) to calculate N
 
Last edited:
Physics news on Phys.org
  • #2
What is the P,V and T in an ordinary room?
 
  • #3
malawi_glenn said:
What is the P,V and T in an ordinary room?

Room temperature is around 21 degrees celsius, P=1.01*10^5 pascals, and I guess in order to get the volume, I assume the room is equal to the shape of a cube and the length of an average room is around 25 meters. I can now calculate my volume by cubing the length of the side of the room./
 
  • #4
Benzoate said:
Room temperature is around 21 degrees celsius, P=1.01*10^5 pascals, and I guess in order to get the volume, I assume the room is equal to the shape of a cube and the length of an average room is around 25 meters. I can now calculate my volume by cubing the length of the side of the room./


Check what you just wrote.. temp must be in kelvnin, and preassure in Si-units. And you have a VERY large room :P biggern than my house :)


let T = 300K, P = 1*10^5 N/m^2, and an average room is like 2.5m from floor to ceiling and 5m x 5m.
 

1. What is an ideal gas?

An ideal gas is a theoretical concept in physics that describes a gas as a collection of molecules that do not interact with each other and have no volume. It follows the ideal gas law, which states that the pressure, volume, and temperature of an ideal gas are related by the equation PV = nRT, where P is pressure, V is volume, n is the number of moles, R is the gas constant, and T is temperature.

2. How is the behavior of an ideal gas different from a real gas?

An ideal gas assumes that there are no intermolecular forces between the gas particles, which is not the case for real gases. Real gases also have non-zero volume, while ideal gases have zero volume. In addition, real gases may undergo phase changes, while ideal gases do not.

3. What is the significance of the ideal gas law?

The ideal gas law is a fundamental equation that helps us understand the behavior of gases and make predictions about their properties. It is also used in many practical applications, such as in thermodynamics, chemistry, and engineering.

4. Can the ideal gas law be applied to all gases?

No, the ideal gas law is only applicable to gases that behave ideally, which means they have negligible volume and do not interact with each other. Real gases, such as those at high pressures or low temperatures, may deviate from ideal gas behavior and require more complex equations to describe their behavior.

5. How does temperature affect the behavior of an ideal gas?

According to the ideal gas law, temperature is directly proportional to the average kinetic energy of the gas particles. As temperature increases, the particles move faster and collide more frequently, resulting in an increase in pressure and volume. On the other hand, as temperature decreases, the particles move slower and collide less, leading to a decrease in pressure and volume.

Similar threads

Replies
24
Views
2K
Replies
3
Views
999
  • Advanced Physics Homework Help
Replies
1
Views
2K
  • Advanced Physics Homework Help
Replies
6
Views
3K
  • Advanced Physics Homework Help
Replies
1
Views
3K
Replies
0
Views
700
  • Advanced Physics Homework Help
Replies
6
Views
4K
  • Advanced Physics Homework Help
Replies
2
Views
2K
  • Advanced Physics Homework Help
Replies
9
Views
1K
Replies
2
Views
552
Back
Top