CHEMISTRY IN THE NINETEENTH CENTURY
Clark’s Standard Cell
A form of wet-chemical cell [more informally, “battery”]producing a highly stable voltage once used as a standard for electromotive force
Clark cells use a zinc, or zinc amalgam, anode and a mercury cathode in a saturated aqueous solution of zinc sulfate, with a paste of mercurous sulfate as depolarizer.
Upper graphic: X - 1891: Benson John Lossing, ed. The New Popular Educator (London, England: Cassell & Company Limited)
Lower graphic: X - 1897: Physikalisches Praktikum mit besonderer Berücksichtigung der physikalischen-chemischen Methoden - von Eilhard Wiedemann und Hermann Ebert; Braunschweig, Friedrich Vieweg und Sohn; 1897
BATTERY: a device that converts chemical energy directly to electrical energy.
MOST BASIC COMPONENT OF A BATTERY: two half-cells that are connected by a conductive electrolyte.
- One half-cell includes electrolyte and the electrode to which anions (negatively charged ions) migrate, i.e., the anode or negative electrode
- The other half-cell includes electrolyte and the electrode to which cations (positively charged ions) migrate, i.e., the cathode or positive electrode. [ X ]