# Collisions of molecules

1. May 27, 2008

### fredrick08

[SOLVED] collisions of molecules..

1. The problem statement, all variables and given/known data
a 10cm^3 box contains nitrogen at 20degreeC. What is the rate of collisions on one wal of he box.

2. Relevant equations
kb=1.38x10^-23
1u=1.661x10^-27
molecular mass of N2=28u
vrms=sqrt((3kbT/m))
rate of collisions=(1/2)(N/V)Av
3. The attempt at a solution
omg i got no idea where even start with this one... im pretty sure i could do it if they gave me the mass of the gas or the number of molecules...... but im just stuck.... y do they give me avagdros number????? im srry im just really confused bout this one... anyone plz help??

2. May 27, 2008

### fredrick08

n=N/Na?? but i dont know n???

3. May 27, 2008

### gendou2

Remember, an ideal gas (such as N2) has a molar volume of 22,400 cubic centimeters per mole at STP (Avogadro's Law).

We know the volume of the box, so we know how many moles of ideal gas there are at 20°C, so we know how many molecules there are.

Last edited: May 27, 2008
4. May 27, 2008

### fredrick08

oh ok ty

5. May 28, 2008

### gendou2

You're very welcome.
Once you're satisfied with the problem, please change the title to "[SOLVED] Collisions of molecules".
Good luck!