Answer
The pressure is roughly $1066.3$ mm Hg.
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. Also we must convert the temperature into Kelvin by simply adding 273.15 to the Celcius value: $T = 45^{\circ}C+273.15 = 318.15 K$ 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{0.0115 mols \times 0.08206 \frac{L\times atm}{mol\times K} \times318.15 K}{0.214 L} = 1.40296 atm $ Since the question asks for the pressure in mm Hg we must convert from the units of atm to mm HG by the following conversion factor: $1.40296 atm\times\frac{760 mm Hg}{1atm} = 1066.254897295 mm Hg$
