Question

If He gas has an average kinetic energy of 4070 J/mol under certain conditions, what is the root mean square speed of O2, gas molecules under the same conditions?

Answer 1

16 m / s

Step-by-step explanation:

Average kinetic energy of one mole of a gas is given by the expression

K.E = 3 / 2 R T { T is absolute temperature of the gas }

Putting the values , we get

4070 = 3 / 2 X 8.312 X T

T = 326.35 K

Under similar condition temperature of oxygen will also be same . So temperature of oxygen gas will be 326.35 K.

Now ,RMS value of a gas =
`\sqrt{(3RT)/(M) }`

T is absolute temperature of gas and M is molecular mass.

Molecular mass of oxygen is 32 gm . T is 326.35

RMS speed =
`\sqrt{(3* 8.314*326.35 )/(32) }`

= 16 m / s . approx.