William Nicholson
Explanation
The phenomenon described is the chemical effect of electric current, specifically the process of electrolysis, where electrical energy is used to drive a non-spontaneous chemical reaction (decomposition of water).
Historical Context and Scientific Contribution:
- William Nicholson (1800): Shortly after the invention of the electric battery, British scientist William Nicholson, along with Anthony Carlisle, performed an experiment where they passed an electric current through water. They observed that bubbles of gas were produced at the electrodes.
- Observation: They demonstrated that oxygen bubbles formed at the electrode connected to the positive terminal (anode), and hydrogen bubbles formed at the electrode connected to the negative terminal (cathode). This established that water could be decomposed into its constituent elements by electricity.
Analysis of Other Options:
- Alessandro Volta: He invented the Voltaic Pile (the first electric battery) in 1800, which provided the continuous source of current used by Nicholson for his experiment. However, Volta himself is credited with the source of current, not the specific discovery of water decomposition.
- Michael Faraday: While Faraday made immense contributions to the field later in the 19th century, including the Laws of Electrolysis which quantify the relationship between current and mass of substance deposited, the initial demonstration of water decomposition predates his work.
- Thomas Edison: He is primarily associated with the invention of the practical incandescent light bulb and the development of direct current (DC) power distribution systems, not the discovery of electrolysis.
Key Takeaway:
William Nicholson is credited with the discovery of the chemical effect of electric current by demonstrating the decomposition of water into hydrogen and oxygen.