Molar Mass = 56 g.mol⁻¹
Data Given:
Mass = 5.00 μg = 5.0 × 10⁻⁶ g
Number of Molecules = 5.38 × 10¹⁶ Molecules
Step 1: Calculate Moles of 1-Butene:
As we know one mole of any substance contains 6.022 × 10²³ particles (atoms, ions, molecules or formula units). This number is also called as Avogadro's Number.
The relation between Moles, Number of Particles and Avogadro's Number is given as,
Number of Moles = Number of Particles ÷ 6.022 × 10²³
Putting values,
Number of Moles = 5.38 × 10¹⁶ Molecules ÷ 6.022 × 10²³
Number of Moles = 8.93 × 10⁻⁸ Moles
Step 2: Calculate Molar Mass of 1-Butene:
As,
Mole = Mass ÷ M.Mass
Solving for M.Mass,
M.Mass = Mass ÷ Mole
Putting values,
M.Mass = 5.0 × 10⁻⁶ g ÷ 8.93 × 10⁻⁸ mol
M.Mass = 55.99 g.mol⁻¹ ≈ 56 g.mol⁻¹
