Polonium were marketed by Firestone from 1940 to 1953. While the amount of radiation from the plugs was minuscule and not a threat to the consumer, the benefits of such plugs quickly diminished after approximately a month because of polonium's short half-life and because buildup on the conductors would block the radiation that improved engine performance. (The premise behind the polonium spark plug, as well as Alfred Matthew Hubbard's prototype radium plug that preceded it, was that the radiation would improve ionization of the fuel in the cylinder and thus allow the motor to fire more quickly and efficiently.) Polonium is
Polonium dioxide a pale yellow, voluminous precipitate, is formed. Despite its name, polonous acid is an amphoteric compound, reacting with both acids and bases. Halogenation of polonium dioxide with the hydrogen halides yields the polonium tetrahalides: In reactions, polonium dioxide behaves very much like its homologue tellurium dioxide, forming Po(IV) salts; however, the acidic character of the chalcogen oxides decreases going down the group, and polonium dioxide and polonium(IV) hydroxide are much less acidic than their lighter homologues. For example, SO, SO, SeO, SeO and TeO are acidic, but TeO is amphoteric, and PoO, while amphoteric, even shows some basic character. The