What is the average speed of gas molecules in a given volume and pressure?

[hatcheezy]

Homework Statement

The mass of a single HE atom is 6.65e-27kg. You have 5.00e-6 mole of HE gas which is occupying a volume of 1.00e-4m^3. when at pressure of 100Pa. Determine the temp of gas AND the average speed of the gas molecules.

**I've found the temp of gas i need help on the avg speed - i believe I'm close

Homework Equations

Vrms=\sqrt{3(R)(T)/(M)}

The Attempt at a Solution

Vrms=\sqrt{3(8.31J/mol K)(241)/(6.65e-27kg?)}

i'm not certain if i use 6.65e-27kg as molar mass?

 

[RoryP]

Homework Statement

The mass of a single HE atom is 6.65e-27kg.

Note it gives you the mass of a single atom

You have 5.00e-6 mole of HE gas

This is the amount of moles present

i'm not certain if i use 6.65e-27kg as molar mass?

After reading the above do you still think this?

 

[RoryP]

ahh i do apologise i had not realized you have calculated the temperature, please ignore the post above