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Ideal Gas Equation, relative molecular mass?

I'm alright with these questions but this question seems to be odd since it wants me to find something different.

At 273K 101000Pa, 6.319g of a gas occupies 2.00 dm^3. Calculate the relative molecular mass of the gas."

I think that firstly you would convert the dm^3 into m^3.

But I'm thinking this is a trick question because no value is given for moles and that it could potentially be a way of indirectly saying to find the number of moles in this gas. But then why would add in a mass for the gas as a value if we aren't using it?
This expects you to know that at 273K and 101kPa (101000 Pa) (STP), 1 mole of gas occupies 22.4 dm3.
Therefore you can calculate the number of moles of gas in this sample and calculate the Mr using the mass.
(edited 9 years ago)

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