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Compute the quantum volume for an N2molecule at room temperature, and argue that a gas of such molecules at atmospheric pressure can be

treated using Boltzmann statistics. At about what temperature would quantum statistics become relevant for this system (keeping the density constant and pretending that the gas does not liquefy)?

Short Answer

Expert verified

The quantum volume for an N2molecule at room temperature is 6.910-33m3. The temperature of system at which quantum statistics become relevant is 5.681K.

Step by step solution

01

Step 1. Formula quantum volume

Formula for quantum volume is:

Q=h2蟺尘办罢3

where,Tis temperature,role="math" localid="1647248715772" mis molecule mass,his Planck's constant,kis Boltzmann constant.

02

Step 2. Calculation quantum volume

Mass of N2 is calculated as:

role="math" localid="1647249031293" m=(28u)1.6710-27kg1u=46.4810-27kg

Substitute variables in quantum volume formula:

Q=6.6310-34Js2(46.4810-27kg)(1.3810-23J/K)(300K)3=6.6310-34347.9110-503=6.910-33m3

So, quantum volume ofN2molecule is6.910-33m3.

03

Step 3. Calculation ideal gas equation

Ideal gas equation is PV=NkT

So, VN=kTP

Substitute Pressure,P=1.013105N/m2, Temperature,T=300K.

role="math" localid="1647253225593" VN=(1.3810-23J/K)(300K)1.013105N/m2=410-26m3

04

Step 4. Calculation temperature

In quantum statistics, VNQ

kTPh2蟺尘办罢3T.T32h3(2蟺尘碍)32PkT52Ph3(2蟺尘)32k52T1kP2h6(2蟺尘)315

Substitute the values of variables in above equation:

T11.3810-23J/K(1.013105N/m2)2(6.6310-34Js)6(2(281.6710-27kg))315T=5.681K

So, temperature of the system is5.681K.

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