Question

How many moles of oxygen must be placed

in a 3.00 L container to exert a pressure of 2.00 atm at 25.0°C?

I did (2.00)(3.00) divded by (0.0821) (298) and I'm still getting the answer as 27,700 or something like that. I know I did the equation right? But, I keep getting the wrong answer. Help please.

Answer 1

Answer: 0.24 moles

Explanation: Using IDEAL GAS LAW

PV=nRT

where,

P = pressure of the gas= 2.0 atm

V = volume of the gas= 3.00L

T =Temperature of gas=25^0C=(25+273)K=298K

n = number of moles of gas=?

R = Gas constant = 0.0821 Latm/moleK

n=\frac {PV}{RT}=\frac {2.0\times 3.0}{0.0821\times 298}=0.24moles