To the Contemporary World

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Why an open flame is a hazard when charging an automobile battery. The typical auto battery is a lead acid battery in which sulfuric acid is the electrolyte. When the battery is charged, hydrogen gas can form at the cathode. This is not a big problem if you use a "trickle" charge (i.e., low-current battery charger) in a well-ventilated space. Hydrogen gas is produced at a slow rate; ventilation allows most of it to escape, thereby preventing an explosive mixture. However a "fast" charge (i.e., high-current battery charger) produces hydrogen at a fairly rapid rate. In a poorly ventilated area, the concentration of hydrogen gas can increase to the point where explosive mixtures are formed.

Community

1. Field trips. Electroplating companies, jewelry makers, electronic firms, chromeplating firms, battery companies

2. Knowledgeable individuals. Electroplating and electrolysis workers, individuals in battery industry, silversmiths

3. Other community resources. Local colleges/community colleges, any analytical chemistry laboratory using ion-specific electrodes

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