The speed of molecules
Answers are for parents and teachers.
1
Estimate the root-mean-square speed of helium atoms (M = 0.004 kg/mol) at 27 °C.
about 1.4·10³ m/s
2
By what factor must the temperature increase to triple the speed?
9
3
Nitrogen and oxygen molecules are at 300 K. Which are faster and why?
Nitrogen (M = 28 < 32): v ∝ 1/√M.
4
If a molecule’s kinetic energy is 6.21·10⁻²¹ J, what is the gas temperature?
300 K
5
Which two ideas does Stern’s experiment confirm?
The molecular-kinetic theory and the Maxwell speed distribution.