The chemical reaction between two or more materials that produces heat, flames, and toxic smoke is described as what?

The chemical reaction between two or more materials that produces heat, flames, and toxic smoke is described as what?

• A. Endothermic heat reaction
• B. Exothermic reaction
• C. Pyrolysis
• D. Chemical free radicals

Answer: (B)

When fuels burn, energy is released as heat, light, and smoke. That release of heat driving the flames is the hallmark of an exothermic reaction. In a fire, the exothermic chemical reaction between the fuel and an oxidizer not only raises the temperature enough to keep the flames going, but the incomplete combustion often produces toxic smoke as a byproduct. Endothermic reactions absorb heat and wouldn’t sustain flames under typical fire conditions. Pyrolysis describes the thermal decomposition of a material into volatile gases that can feed later burning, but it’s a heating process that precedes combustion rather than the actual burning reaction itself. Chemical free radicals aren’t a kind of reaction; they’re reactive species formed during combustion that help propagate the flames.

When fuels burn, energy is released as heat, light, and smoke. That release of heat driving the flames is the hallmark of an exothermic reaction. In a fire, the exothermic chemical reaction between the fuel and an oxidizer not only raises the temperature enough to keep the flames going, but the incomplete combustion often produces toxic smoke as a byproduct.

Endothermic reactions absorb heat and wouldn’t sustain flames under typical fire conditions. Pyrolysis describes the thermal decomposition of a material into volatile gases that can feed later burning, but it’s a heating process that precedes combustion rather than the actual burning reaction itself. Chemical free radicals aren’t a kind of reaction; they’re reactive species formed during combustion that help propagate the flames.