🔍 Key Concepts

• Difference between hydrocarbon fuels (like gasoline, crude oil, jet fuel) and polar solvents (like alcohol) • How regular foam (non–alcohol-resistant foam) works to smother a flammable liquid fire • Which liquids will dissolve or destroy regular foam, preventing a stable foam blanket

💭 Think About

• Ask yourself: Which of these liquids mixes easily with water and could therefore break down a water-based foam? • Which of these fuels are typical hydrocarbons that standard foam is designed to blanket and smother? • Think about fire-fighting classes: which type of liquid needs a special alcohol‑resistant foam, not regular foam?

✅ Before You Answer

• Identify which option is a polar solvent (water-miscible) rather than a straight hydrocarbon • Confirm which liquids standard foam is normally recommended for: Class B hydrocarbon fuels • Before choosing, verify which liquid would most likely destroy or thin out a standard foam blanket instead of supporting it