HI! I am having trouble answering this question and getting the right answer (2) At 10 K, the molecules in a gas have an average kinetic energy of 2 x 10-22J. Would quantum mechanical effects be important to understand the motion of helium atoms at this temperature? Solution According to de-Broglie\'s concept, Wave length = h / ( m V ) And Kinitic energy, K.E = 1/2 mV 2 Substituting V value from K.E, wave length = h / sqrt(2 * K.E. m) = 6.626 * 10 -34 / sqrt( 2 * 2 * 10 -22 * 4 * 1.66 * 10 -27 ) Wave length = 4.06 * 10 -10 m = 4.06 * 10 -8 cm = 4.06 A 0 So, It has a measurable quantity of wave length, quantum mechanical effects are very important to understand the motion of He atoms. .

1. HI! I am having trouble answering this question and getting the right answer
(2) At 10 K, the molecules in a gas have an average kinetic energy of 2 x 10-22J. Would
quantum mechanical effects be important to understand the motion of helium atoms at this
temperature?
Solution
According to de-Broglie's concept,
Wave length = h / ( m V )
And Kinitic energy, K.E = 1/2 mV 2
Substituting V value from K.E,
wave length = h / sqrt(2 * K.E. m) = 6.626 * 10 -34
/ sqrt( 2 * 2 * 10 -22
* 4 * 1.66 * 10 -27
)
Wave length = 4.06 * 10 -10
m = 4.06 * 10 -8
cm = 4.06 A 0
So, It has a measurable quantity of wave length, quantum mechanical effects are very important
to understand the motion of He atoms.