PVC's Empirical Formula Matches Monomer's

Steps:

• Identify PVC as poly(vinyl chloride), formed by polymerization of vinyl chloride monomer (CH₂=CHCl).
• Determine empirical formula of monomer: simplest ratio is CH₂Cl (C:H₂:Cl).
• Recall PVC's repeat unit as –(CH₂CHCl)– , with empirical formula CH₂Cl.
• Compare: both share the same empirical formula, confirming B.

Why B is correct:

• Empirical formula represents simplest atom ratio; PVC's repeat unit (CH₂CHCl) simplifies to CH₂Cl, identical to the monomer's.

Why the others are wrong:

• A: PVC combustion yields HCl (acidic), not alkaline, making fumes harmful due to acidity.
• C: PVC chains are saturated (single C-C bonds post-polymerization), not unsaturated.
• D: Repeat unit is –CH₂CHCl–, but written without dashes; however, it's not just (CH₂CHCl) as a standalone formula.

Final answer: B