Question

A mixture of 2 moles of helium gas (atomic mass = 4 amu) and 1 mole of argon gas (atomic mass = 40 amu) is kept at 300 K in a container. The ratio of the r m s speeds is






A)
0.32




B)
0.45




C)
2.24




D)
3.16




View Solution Answer: D Solution:
As we know that

where R = gas constant

T = temperature of the gas

M = molecular mass of the gas

Now MHe (molecular mass of Helium) = 4

M­Ar (molecular mass of Argon) = 40



in this question, why don't we consider the mass of 2 moles of helium?

Answer 1

Option d3.16 is right answer