# Whats the mass of the sample?

#### Dx

Hi!

A simple He occupies 44.8L at STP. what is the mass of the sample?

my answer was 4g since the atomic mass is 4u but im wrong. someone/anyone enlighten me towards the right path so I may be one again.
Thanks!
Dx

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#### Bystander

Homework Helper
Gold Member
44.8 L at STP is how many moles?

#### Dx

Originally posted by Bystander
44.8 L at STP is how many moles?
I donno? the question doesnt say. nor can i find out how to compute that since i dont have the mass.

#### Bystander

Homework Helper
Gold Member
Somewhere in the text or lectures for your course, it has been stated, " One mole of an ideal gas occupies 22.4 L at STP." If it ain't been said outright to you previously, it has now. One mole also contains Avogadro's number of molecules, 6.02x10E23. This should have you in business on this and your other posted question. If not, holler.

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