Answer:
d = 1.8 × 10⁻⁴ kg/L
Step-by-step explanation:
Given data:
Moles of helium = 2 mol
Temperature and pressure = standard
Density = ?
Solution:
PV = nRT
V = nRT/ P
V = 2 mol × 0.0821 atm. L/ mol. K × 273 K / 1 atm
V = 44.8 L
Mass of helium:
Mass = number of moles × molar mass
Mass = 2 mol × 4 g/mol
Mass = 8 g
Mass = 0.008 kg
Density;
Density = mass/ volume
d = 0.008 kg/ 44.8 L
d = 1.8 × 10⁻⁴ kg/L