At standard temperature and pressure, or STP, the volume of 4.50 moles of nitrogen gas is 100.8 liters. In chemistry, the volume or space that 1 mole of any gas occupies at STP is given as 22.4 liters, or 22.4 liters/1 mol. By using this information, the calculation to find the volume of 4.5 moles involves multiplying 4.5 mole by 22.4 liters/1 mol.
Another method to find the answer is by using the Ideal Gas Law given as P x V = n x R x T, where at STP, the temperature is 32 degrees Fahrenheit or 273 degrees Kelvin, the constant R is 0.082057 L atm/mol K degrees, n is the number of moles and P is the pressure of 1 atm. By expressing the Ideal Gas Law as V = (n x R x T) and substituting for the variables n = 4.5, T =273 K, R= 0.082057, P= 1 atm, it is possible to find the volume as 100.8 L.