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I'm stuck on two questions, I gratefull if someone could help me with them, firstly;

(Q1) "A cubical container of volume 0.10m^3 contains a gas at 300K and 1000000Pa. Assuming that the gas is ideal, determine

a) the number of moles of gas present, given that the Universal Gas constant is 8.3 J/K/mol.

b) the mass of gas present given that its relative molecular mass is 352.

c) the density of the gas"

I'm okay I think working out 1a I used the equation n=PV/RT and got 22.22. I can't seem to find how to work out the mass...and 1c I think I'm okay, I guess I just use M/V.

Secondly;

(Q2) "A fixed mass of gas in passing through a jet engine has its pressure increased from 300000 to 1300000Pa, while its temperature rises from 80(deg C) to 1500 (deg C). By what factor does the volume of gas change?"

I worked out an answer to this but it looks wrong, I used P1/T1 = P2/T2 and found the difference between those two to be 116.638, so is that the correct method to work out the change of volume?

Thanks again

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# Homework Help: Thermodynamics/Gas Law questions

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