Answer:
Molecular Formula = C₁₀H₈
Explanation:
Step 1: <u>Calculating Moles for each Element:</u>
C = Mass of CO₂ × (1 mol of CO₂÷ M.Mass of CO₂) × (1 mol of C ÷ 1 mol of CO₂)
C = 8.60 g × (1 mol of CO₂÷ 44.011 g.mol⁻¹) × (1 mol of C ÷ 1 mol of CO₂)
C = 0.1954 mol
H = Mass of H₂O × (1 mol of H₂O ÷ M.Mass of H₂O) × (2 mol of H ÷ 1 mol of H₂O)
H = 1.41 g × (1 mol of H₂O ÷ 18.106 g.mol⁻¹) × (2 mol of H ÷ 1 mol of H₂O)
H = 0.1557 mol
Step 2: <u>Calculate the Smallest whole number ratio as,</u>
C H
0.1954 0.1557
0.1954/0.1557 0.1557/0.1557
1.25 1
Multiply ratio by 4,
5 4
Result:
Empirical Formula of Propane is C₅H₄
Step 3: <u>Calculate Molecular Formula:</u>
Molecular formula is calculated by using following formula,
Molecular Formula = n × Empirical Formula ---- (1)
Also, n is given as,
n = Molecular Weight / Empirical Formula Weight
Molecular Weight = 128.0 g.mol⁻¹
Empirical Formula Weight = 5 (C) + 4 (H) = 64 g.mol⁻¹
So,
n = 128.0 g.mol⁻¹ ÷ 64 g.mol⁻¹
n = 2
Putting Empirical Formula and value of "n" in equation 1,
Molecular Formula = 2 × C₅H₄
Molecular Formula = C₁₀H₈
