What happens to a glowing splint in an environment containing carbon dioxide?

• A. Reignites
• B. Glows brighter
• C. Extinguishes
• D. No effect

Answer: (C)

Combustion needs oxygen. A glowing splint stays lit or reignites when there is enough oxygen around; it will fade if there isn’t. Carbon dioxide does not support combustion and can displace air, so there isn’t enough oxygen for the splint to continue glowing. The result is that the splint is extinguished.

That’s why this environment causes the glowing splint to go out rather than reignite, glow brighter, or remain unchanged. Carbon dioxide is commonly used to put out fires because it removes the oxygen needed for flame.