Answer:
4.549 kg.
Step-by-step explanation:
- We can use the general law of ideal gas: PV = nRT.
where, P is the pressure of the gas in atm (P = 2 x 10⁴ kPa/101.325 = 197.4 atm).
V is the volume of the gas in L (V = 20.0 L).
n is the no. of moles of the gas in mol (n = ??? mol).
R is the general gas constant (R = 0.0821 L.atm/mol.K),
T is the temperature of the gas in K (T = 23° C + 273 = 296 K).
∴ n = PV/RT = (197.4 atm)(20.0 L)/(0.0821 L.atm/mol.K)(296 K) = 162.5 mol.
- To find the mass of N₂ in the cylinder, we can use the relation:
mass of N₂ = (no. of moles of N₂)*(molar mass of N₂) = (162.5 mol)*(28.0 g/mol) = 4549 g = 4.549 kg.