Answer
The pressure is $0.911 atm$
Work Step by Step
Using the ideal gas law $PV = nRT$ where "P" is the pressure the gas exerts, "V" is the volume the gas occupies, "n" represents the number of moles of the gas, "R" is the ideal gas constant and "T" represents the temperature, we can solve many gaseous questions that behave in ideal conditions.
The question asks for $P$ so we must isolate for the volume from the ideal gas equation to obtain $P = \frac{nRT}{V}$
$P = \frac{0.683 mols \times 0.08206 \frac{L\times atm}{mol\times K}\times 325 K}{20.0 L} = 0.911 atm$