Question

Oxygen O2O2 has a molar mass of 32.0 g/molg/mol. What is the average translational kinetic energy of an oxygen molecule at a temperature of 299 KK ?

A- Suppose an oxygen molecule traveling at this speed bounces back and forth between opposite sides of a cubical vessel 0.17 mm on a side. What is the average force the molecule exerts on one of the walls of the container? (Assume that the molecule's velocity is perpendicular to the two sides that it strikes.)

B- What is the average force per unit area?

Answer 1

Answer: The average translational kinetic energy of an oxygen molecule is 3 KBT where, KB : Boltzman constant. = 1.38 X10-23 m?kas-ZK-', Kibongo = x 1.38 X10-23 x 299 = 6.189x10+21 J VID Average force on one of the walls . Change of momentum F = = Time duration ap=mo-(-mo)=zmo +0.17mm> = 17x10 m =2 at = 21 So, F= 2m = more Now, average translational Kinetic energy, hmor=2 / 22 KT I mor=3KT F= 3KT - 3 X1.38 410-23x299 L 17x10-5 = 7.281410-17 N. Forne - ETO per unit area : Area of one walls 7:281710-17 - Pressure, p= = 2 = (17x10-5 m² Ã = = 17x10-52 2.519 x109 Nine