What Is the Average Kinetic Energy of a Nitrogen Molecule at 25°C?

AI Thread Summary
The average kinetic energy of a nitrogen molecule at 25°C is calculated using the formula KE = 3/2 kT, where k is the Boltzmann constant. The calculated value is approximately 6.17 x 10^(-21) J, which suggests that the provided answer choices may not include the correct answer. A clarification was made that a nitrogen molecule, being diatomic, can also rotate, affecting its kinetic energy calculation. The discussion also mentions that the kinetic energy formula can be adjusted to K.E = 5/2 kT for diatomic molecules. The final consensus indicates that the initial answer choices were likely incorrect.
M9501
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Homework Statement


The average kinetic energy of a nitrogen molecule at temperature 25c is _____ .

Select the correct answer.
1)5*10^(-21) J
2)3*10^(-20) J
3)1*10^(-20) J
4)9*10^(-20) J
5)8*10^(-21) J
(i guess they are all wrong )

Homework Equations


KE=3/2 K.T

The Attempt at a Solution



KE(av)=3/2 KT = 3/2 * 1.38*10^(-23) * (25+273)=6.1686*10^(-21) J

i just want to know whether my solution is correct or no ..
 
Physics news on Phys.org
A nitrogen molecule is not a single atom. It can rotate...
 
mfb said:
A nitrogen molecule is not a single atom. It can rotate...
got it thanks

K.E=5/2 KT
 

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