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The electrical conductivity of lead dioxide has been measured for dense samples prepared by the electrolysis of lead perchlorate and other lead salts and for porous samples prepared from storage battery oxides and from pressed powder. The specific resistance of the dense samples is of the order of 2×10−4 normalohm‐normalcm . That of the battery material is 74×10−4 normalohm‐normalcm . The resistance increases with temperature by about 0.2 per cent per degree at room temperature.Amechanism for conduction is proposed which assumes that lead dioxide is not of exact stoichiometric composition, but contains an excess of lead, which is considered to be dissociated into tetravalent lead ions and free electrons. The conductivity is due to the latter. Hall effect measurements have been made from which the density of carriers is shown to be about 4.4×1020/cm3 . or 1.8×10−2 carriers per molecule.

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