Thursday

July 31, 2014

July 31, 2014

Posted by **Kamila** on Monday, March 21, 2011 at 11:40pm.

What is the molar mass of gas Y?

(V and T constant)

- chemistry -
**Joanie**, Monday, March 21, 2011 at 11:55pmOk so i also was going to ask this question but I THINK i figured it out.

remember that mols and pressure are proportional. if 1 mol of O2 gives 2 atm of pressure, then how many mols of a gas gives 1 atm of pressure? (because the total is three, so we just need to find out how to get that extra atm of pressure). so i set up a proportion. 1mol/2atm=Xmol/1atm and i got .5 so then i set up 60g Y/.5 mol and i got 120. it makes sense but im not sure if this is how it was supposed to be done. i did get the right answer so i hope i helped a little!

- chemistry -
**DrBob222**, Tuesday, March 22, 2011 at 12:39amYes, 120 is correct.

I worked it with mole fractions.

XO2 = (PO2/Ptotal) = (2/3)

Xunk = (Punk/Ptotal) = (1/3)

Then for oxygen, (1 mol)

(mol O2/(mol O2 + mol unk) = 2/3

Solve for mole unk, then moles = g/molar mass and solve for molar mass.

Your solution is more esoteric than mine.

**Related Questions**

Chemistry - Container A holds 752 mL of ideal gas at 2.40 atm. Container B holds...

chemisrty - Q6) A 10 L container contains a mixture of 0.8 g of He and 8 g of Ar...

chemistry - Three gases (8.00 of methane, 18.0 of ethane, and an unknown amount ...

Chemistry - Three gases (8.00 of methane,CH4 , 18.0 of ethane,C2H6 , and an ...

CHEMISTRY - A 44.1 L sample of nitrogen gas at a pressure of 88.3 kPa is placed ...

physics - A closed container with a volume of 8000cm^3 is filled with Xenon gas...

chemistry - Container A holds 767 mL of ideal gas at 2.50 atm. Container B holds...

Chemistry - Three gases (8.00 of methane, , 18.0 of ethane, , and an unknown ...

chemistry - Three gases (8.00 of methane, , 18.0 of ethane, , and an unknown ...

chemistry - A 12 g sample of Ne is added to a container that also holds .78 mol ...