(excerpted from “Using lecture demonstrations to promote the refinement of concepts: the case of teaching solvent miscibility”, - 85041.pdf ). “I still recall the very first time I ever saw a chemical demonstration on the overhead projector. It was more than 25 years ago, and the demonstrator was Clark Bricker from the University of Kansas. He added a few drops of ammonia to a solution containing ferric ions. The beauty, simplicity, and clear visibility of that demonstration impressed me so much that I have been doing demonstrations … ever since.” ~ Doris Kolb (excerpted from “The purpose of chemical demonstrations”, %20demoproeven.pdf ) “The joy of chemical experimentation has been well recognized, at least from the early days of alchemy, and our appreciation of chemical charm probably dates back to the prehistoric discovery of ways to make and control fire. Therefore, it seems useful to coin the term exocharmic reaction (from the Greek exo-, turning out) and, particularly in our role as chemistry teachers, to seek and share techniques for liberating as much charm as possible from the chemical changes our students see in the laboratory and classroom demonstrations.” ~ Richard Ramette (excerpted from the introduction to Volume 1 of Bassam Shakhashiri's Chemical Demonstrations: A Handbook for Teachers of Chemistry ) More on the history of the candle demonstration Michael Faraday is credited with doing the first large-scale demonstration(s) involving the burning of a candle. In 1848 he presented a series of six lecture-demonstration sessions, The Chemical History of a Candle , at the Royal Institution in London, U.K. This series, part of a long-running (1825–present) series of lectures at the Royal Institution is called the Christmas Lectures. Faraday presented his lecture-demonstrations to school-aged children, to popularize science, and chemistry in particular. He then (1861) had the six lectures assembled into a book by the same title. The book is still available today, both in print and online. ( ) 31
The content of the Six Lectures included: Lecture 1: A Candle: The Flame - Its Sources - Structure - Mobility - Brightness Lecture 2: Brightness of the Flame - Air necessary for Combustion - Production of Water Lecture 3: Products: Water from the Combustion - Nature of Water - A Compound - Hydrogen Lecture 4: Hydrogen in the Candle - Burns into Water - The Other Part of Water - Oxygen Lecture 5: Oxygen present in the Air - Nature of the Atmosphere - Its Properties - Other Products from the Candle - Carbonic Acid - Its Properties Lecture 6: Carbon or Charcoal - Coal Gas Respiration and its Analogy to the Burning of a Candle - Conclusion ( ) A recent ChemMatters article provided a thorough description of the history and chemistry of candles (Rohrig, B. The Captivating Chemistry of Candles. ChemMatters 2007 , 25 (4), pp 4–7). Information from that article on the basic chemistry of candles includes:
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