Answer:
Molar mass = 1.111 × 10⁻⁵ g/mol
Explanation:
Given data:
Mass of polyethylene = 1.36 g
Volume = 100 mL (0.1 L )
Pressure = 1.86 torr (1.86/760 = 0.003 atm)
Temperature = 25 °C = 25 °C + 273.15 = 298.15 K
Molar mass of polyethylene = ?
Solution :
PV =nRT
n = PV/RT
n = 0.003 atm × 0.1 L / 0.0821 atm. L . mol⁻¹ .k⁻¹ × 298.15 k
n = 0.0003 atm. L / 24.5 atm. L . mol⁻¹
n = 1.2245 × 10⁻⁵ mol
Molar mass = mass / number of moles
Molar mass = 1.36g / 1.2245 × 10⁻⁵ mol
Molar mass = 1.111 × 10⁻⁵ g/mol
