How do I find the average kinetic energy of an atoms at temp 5700K?

Question

The surface of a star consists mostly of hydrogen atoms (not molecules) at a temperature of 5700 K.

What are the average translational kinetic energy per atom and the rms speed of the atoms?

Answer 1

See the ref. for explanation and formulas.

Mean KE = 3(kB)T/2 = 1.18046160973975E-19 J

v(rms) = sqrt(3RT/M) = 11923.8474069157 m/s

where

M = molar mass of H atom = 0.001

R = universal gas constant = 8.31451093470238 J/(mole-degK)

kB = Boltzmann's constant = R/Avogadro = 1.38065685349678D-23 J/(molecule-degK

Answer 2

KE = (1/2) m*v 2

     v = root of ( gamma* r* T)

      where,  T = temperature

      substitute it u'll get the answer

Answer 3

PV = nRT

PV = (MNC^2)/3 ; C = average speed

so

nRT = (MNC^2)/3

3nRT/2N = (M C^2)/2

(M C^2)/2 = verage translational kinetic energy per atom

therefor

3nRT/2N  = Ke

Ke = 3RT/2L ; L = Avogadro Constent 6.022*10^23

Ke = 3*8.314*5700/(2*6.022*10^23)

1.1804.....j

Hope this Helps

Answer 4

average KE = sqrt( 3kT )

where k is Boltzman const , T is temp in Kelvin