What is the pressure exerted by 100g of oxygen gas in a 20L container at 30.0 C?

Question

ipwnbunnies · Answer

Use the Ideal Gas Equation:
$$PV = nRT$$
P is pressure, V is volume, n is the amount of moles of gas, R is the gas constant, and T is the temperature in Kelvin, in this case.

ipwnbunnies · Answer

The constant, R, we will use is 0.08206 L-atm/mol-K. You have to first convert your given temperature to Kelvin. Then, convert the 100g of oxygen to moles of oxygen.

anonymous · Answer

The temperature becomes 303.15 K.

ipwnbunnies · Answer

Mhm. Now convert the mass to moles.

anonymous · Answer

6.25 moles

perl · Answer

is oxygen diatomic?

ipwnbunnies · Answer

Hmm, it might be incorrect. Oxygen exists as a diatomic molecule, O2.

anonymous · Answer

So 3.125 moles?

ipwnbunnies · Answer

I would suggest to assume the 100g is of diatomic oxygen. && Yesh, 3.125 moles.

ipwnbunnies · Answer

So, now, we can find the pressure of the gas. Go back to the Ideal Gas Equation, solve for P, pressure. Plug in your values.

ipwnbunnies · Answer

Parth. ♥

anonymous · Answer

The pressure is 3.89

ipwnbunnies · Answer

That's the numerical value, but what are the units?

anonymous · Answer

pascals

ipwnbunnies · Answer

Nope. :3   Look back at the gas constant I gave you. Using dimensional analysis, all those things cancel out except one unit.

perl · Answer

molar mass of oxygen is 32 grams /mol

ipwnbunnies · Answer

We already found the moles of O2. ;3

perl · Answer

right, now you just plug in

perl · Answer

actually to be more precise, add 273.15 to degrees celsius

perl · Answer

P = 3.125 moles * 0.08206 * (273.15 + 30) / 20

perl · Answer

pressure will be in atm's i suppose 
I get 3.88695