Answer:
1. The empirical formula => C₆H₁₀OS₂
2. Molecular formula => C₃₆H₆₀O₆S₁₂
Explanation:
1. Determination of the empirical formula.
Carbon (C) = 2.96 g
Hydrogen (H) = 0.414 g
Oxygen (O) = 0.675 g
Sulphur (S) = 2.96 g
Divide by their molar mass
C = 2.96 / 12 = 0.247
H = 0.414 / 1 = 0.414
O = 0.675 / 16 = 0.042
S = 2.96 / 32 = 0.0925
Divide by the smallest
C = 0.247 / 0.042 = 6
H = 0.414 / 0.042 = 10
O = 0.042 / 0.042 = 1
S = 0.0925 /0.042 = 2
Therefore, the empirical formula is
C₆H₁₀OS₂
2. Determination of the molecular formula.
Molar mass of compound = 972 g/mol
Empirical formula => C₆H₁₀OS₂
Molecular formula =>?
Molecular formula = [C₆H₁₀OS₂]ₙ
Molecular formula = molar mass of compound
Thus,
[C₆H₁₀OS₂]ₙ = 972
[(12×6) + (10×1) + 16 + (32×2)]n = 972
[72 + 10 + 16 + 64]n = 32
162n = 972
Divide both side by 162
n = 972 / 162
n = 6
Molecular formula = [C₆H₁₀OS₂]ₙ
Molecular formula = [C₆H₁₀OS₂]₆
Molecular formula = C₃₆H₆₀O₆S₁₂
