A closed container holds 2.0 moles of CO2 gas at STP. How many moles of oxygen can be placed in a container of the same size at STP?

2 moles

Explanation:

STP is Standard Temperature and Pressure. That means the pressure is 1.00 atm and the temperature is 273K. Since the oxygen is placed in the same container, we can use Ideal Gas Law to figure out what container the CO₂ used.

Ideal Gas Law: PV=nRT

P=1.00 atm

n=moles

R=0.08206 Latm/Kmol

T=273K

CO₂

Since we know that CO₂ has a 44.8 L container, we can use that to find the moles of oxygen.

There are 2 mol of oxygen.