Posted by **zuhra** on Wednesday, April 18, 2012 at 2:38pm.

A sealed container contains 1 mole of neon gas at STP. Estimate the number of neon atoms having speeds in the range from 200 m/s to 202 m/s. (Hint: Assume the probability of neon atoms having speeds between 200 m/s and 202 m/s is constant).

- physics -
**Elena**, Wednesday, April 18, 2012 at 5:33pm
STP - Standard Temperature and Pressure - is 273 and 105 Pa

Maxwell distribution for the relative velocities is

ΔN/N = 4/sqrt(π)•(1/e^(u^2))•u^2•Δu,

v1 = 200m/s, v2 =202 m/s, Δv =202-200 = 2m/s.

The most probable velocity

v(pr) = sqrt(2RT/M) = sqrt(2•8.31•273/20•10^-3) = 476.3 m/s.

The relative velocity is

u = v1/v(pr) = 200/476.3 = 0.42,

u^2 = 0.176,

1/e^(u^2)) = 0.838

Δu = Δv/v(pr) = 2/476.3 = 4.2•10^-3.

ΔN/N = 4/sqrt(π)•0.838•0.176•4.2•10^-3 =1.4•10^-3 = 0.0014.

Therefore. 1,4% of the neon atoms have the velocities of 200 – 202 m/s or their absolute number in 1 mole is

ΔN = N•0.0014 = 6.022•10^23•0.0014 = 8.42•10^20

- physics -
**Erica**, Sunday, April 14, 2013 at 11:20pm
This looked a little sloppy imo... Here's my example

1. Find most probably velocity of Krypton

v = √[(2*8.314J/K*273K)/(0.083798 kg)] = 237.75 m/s

Find the ratio of each velocity

205/237.75 = .8808 The average is .8851

207/237.75 = .8894

Find the ratio of change in velocities 207-205

2/237.75 = 0.008593

Then: Find the probability!

6.022e23 molecules * 5 mol * .8851 * 0.008593 = 2.29e22

I just did a problem like this... These are my numbers, but the work is a lot more simple

## Answer This Question

## Related Questions

- physics - A sealed container contains 1 mole of neon gas at STP. Estimate the ...
- chemistry - a sample containing 1.50 mol neon gas has a volume of 8.00L.what is ...
- physics - How much positive charge is in 0.8 kg of neon? The atomic weight (20....
- chemistry - The diameter of a neutral neon atom is about 1.4 ✕ 10^2 pm. ...
- Chemistry - Consider a sample of helium and a sample of neon, both at 30ºC and 1...
- chemistry - a real gas is introduced to a flask of volume v. is the corrected ...
- Chemistry - Which gas has the greatest kinetic energy? a) neon at a temperature ...
- gas laws chemistry - A neon sign is made of glass tubing with an inside diameter...
- chem - The diameter of a neutral neon atom is about 1.4 multiplied by 102 pm. ...
- Chem - One of my questions asks me to find the volume of neon gas. I thought ...

More Related Questions