The Chemical History of a Candle

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A close-up image of a candle showing the wick and the various parts of the flame
Title page to the first edition

The Chemical History of a Candle was the title of a series of six lectures on the chemistry and physics of flames given by Michael Faraday at the Royal Institution. This was the origin of the Christmas lectures for young people that are still given there every year and bear his name.

The lecture described the different zones of combustion in the candle flame, and the presence of carbon particles in the luminescent zone. Demonstrations included the production and examination of the properties of, Hydrogen, Oxygen, Nitrogen and Carbon dioxide gases. An electrolysis cell is demonstrated, first in the electroplating of Platinum conductors by dissolved copper, then the production of Hydrogen and Oxygen gases, and their recombination to form water. The properties of water itself are studied, including its expansion while freezing (iron vessels are burst by this expansion), and the relative volume of steam produced when water is vaporized. Techniques for weighing gases on a balance are demonstrated. Atmospheric pressure is described and its effects demonstrated.

Faraday emphasizes that several of the demonstrations and experiments performed in the lecture may be performed by the children "at home," and makes several comments regarding proper attention to safety.

The lectures were first printed as a book in 1861.

Contents of the Six Lectures[edit]

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

External links[edit]