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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.

Graphite is the stable variety of carbon under standard conditions of temperature and pressure. The carbon atoms are arranged in parallel planes with a hexagonal network of atoms linked by sigma bonds involving sp2 hybrid orbitals and pi bonds involving the remaining p orbital. van der Waals attractions between the graphitic sheets provide the cohesion of the three dimensional structure of graphite. Graphite exfoliation is a well known process in carbon chemistry. An intercalation compound is first synthesized using reactants with strong redox properties. The intercalated graphite is then heated and the exfoliation occurs. A graphite vermicular powder is obtained.