Which statement best defines Explosive?

• A. A chemical that burns steadily without release of heat.
• B. A material that reacts slowly with air.
• C. A substance that releases energy gradually as heat.
• D. Chemical that causes a sudden release of pressure, gas, and heat when subjected to sudden shock, pressure or high temperature.

Answer: (D)

Explosives are materials that release energy extremely quickly, producing a sudden, large rise in pressure and temperature with a burst of hot gas. The key idea is that a brief, energetic trigger—such as sudden shock, heat, or pressure—initiates rapid decomposition or detonation, creating a blast wave. That rapid energy release sets it apart from substances that burn steadily or react slowly with air, which don’t generate the abrupt pressure spike explosive events produce. So a chemical that causes a sudden release of pressure, gas, and heat when subjected to sudden shock, pressure, or high temperature best defines an explosive.