To answer this item, we are to assume that dinitrogen oxide is an ideal gas such that it follows the equation,
PV = nRT
Taking into account the density of the gas,
P = (m/M)RT/V
Substituting the known values,
P = (2.85 g/L)(0.0821 L.atm/mol K)(298 K) / 44 g/mol)
P = 1.58 atm
Each 1 atm is equal to 760 mmHg
Answer: 1204.38 mmHg
