1. Write the balanced chemical equation for the combustion of butane:

C₄H₁₀ (g) + 13/2 O₂ (g) → 4 CO₂ (g) + 5 H₂O (g)

2. Determine the mole ratio between butane and water:

From the balanced equation, we see that 1 mole of butane (C₄H₁₀) produces 5 moles of water (H₂O).

3. Calculate the moles of water produced:

Since we have 5.50 moles of butane, and the mole ratio is 1:5, we can calculate the moles of water produced:

5.50 moles C₄H₁₀ * (5 moles H₂O / 1 mole C₄H₁₀) = 27.5 moles H₂O

Therefore, 27.5 moles of water vapor will be produced when 5.50 moles of butane are reacted.