An efficient composition for bengal lights

Students of inorganic chemistry can learn about solid-phase redox theory by preparing bengal lights using thiourea-potassium chlorate and flame-coloring agents. The lights are used in pyrotechnic shows, but originated when priests in ancient India in the Bengal province pressed mixtures containing strontium salts, charcoal, sulfur, and potassium nitrate into shapes and ignited them in temple gloom where they burned with a colored flame after ignition. Risk exists in this activity, but safety measures have been developed. The difference between deflagration and detonation is discussed.