Answer
m = 15.2 g
Step-by-step explanation
Given:
Volume = 4.50 L
At SATP, meaning
Temperature = 25 °C = 298 K
Pressure = 101.325 kPa = 1 atm
Volume of 1 mole = 24.4651 L
We know R = 8.314m^3-Pa-/mol-K^2 = 0.08206 L.atm/mol.K
Solution
To solve this problem we will use the ideal gas law
PV = nRT
Step 1: Solve for number of moles (n)
n = PV/RT
n = (1 atm x 4.50 L)/(0.08206 L.atm/mol.K x 298 K)
n = 0.184 mol
Step 2: Now that we have the number of moles, we can convert to mass
Molar mass of Krypton gas = 83.7980 g/mol
m = n x M where m is the mass, n is the moles and M is the molar mass
m = 0.184 mol x 83.7980 g/mol
m = 15.4 g which is close to 15.2 g