The coefficients are 2C₄H₁₀ + 13O₂ ⟶ 8CO₂ + 10H₂O
Step 1. Gather all the information in one place.
M_r: 58.12 32.00 44.01 18.02
aC₄H₁₀ + bO₂ ⟶ cCO₂ + dH₂O
m/g: 1.76 0.90
n/mol: 0.010
Step 2. Calculate the mass of C₄H₁₀.
Mass = 0.010 mol C₄H₁₀ × (58.12 g C₄H₁₀/1 mol C₄H₁₀) = 0.581 g C₄H₁₀
Step 3. Calculate the mass of O₂
Mass of C₄H₁₀ + mass of O₂ = mass of CO₂ + mass of H₂O
0.581 g + x g = 1.76 g + 0.90 g
x = 1.76 + 0.90 - 0.581 = 2.079
Our information now has the form:
M_r: 58.12 32.00 44.01 18.02
aC₄H₁₀ + bO₂ ⟶ cCO₂ + dH₂O
m/g: 0.581 2.079 1.76 0.90
n/mol: 0.010
Step 4. Calculate the moles of each compound.
Moles of O₂ = 2.079 g O₂ × (1 mol O₂/32.00 g O₂) = 0.064 97 mol O₂
Moles of CO₂ = 1.76 g CO₂ × (1 mol CO₂/44.01 g CO₂) = 0.040 00 mol CO₂
Moles of H₂O = 0.90 g H₂O × (1 mol H₂O/18.02 g H₂O) = 0.0499 mol H₂O
Our information now has the form:
aC₄H₁₀ + bO₂ ⟶ cCO₂ + dH₂O
n/mol: 0.010 0.064 97 0.040 00 0.0499
Step 5: Calculate the molar ratios of all the compounds.
a:b:c:d = 0.010:0.064 97:0.040 00:0.0499 = 1:6.497:4.000:4.99
= 2 :12.99:8.00:9.98 ≈ 2:13:8:10
∴ a = 2; b = 13; c = 8; d = 10
The balanced equation is
2C₄H₁₀ + 13O₂ ⟶ 8CO₂ + 10H₂O
