Accession Number : AD0830542

Title :   POTENTIOMETRY ON SILVER HALIDE MONOCRYSTALS,

Corporate Author : GENERAL DYNAMICS/ASTRONAUTICS SAN DIEGO CA

Personal Author(s) : Matejec, R.

Report Date : JAN 1959

Pagination or Media Count : 14

Abstract : The electrochemical equilibrium potentials of silver in contact with aqueous silver halide solution (EL) and of silver in contact with a silver halide crystal immersed in the solution (EK) are measured, and their dependence on the silver ion concentration of the solution as well as their change by addition of halide and by exposure are studied. It was found that the EK potential is 210 plus or minus 40 mV more negative than the EL potential for AgCl, and 140 plus or minus 40 mV more negative for AgBr. The requirement that the photographic developer must have a 100-150 mV more negative redox potential for the development of AgBr emulsions than corresponding to the EL potential presumable is mostly due to the difference between EL and EK and not so much to the dependence of the EL potential (silver / silver halide solution) on the size of the developing grain. (Author)

Descriptors :   (*PHOTOGRAPHIC CHEMICALS, ELECTROCHEMISTRY), (*SILVER COMPOUNDS, ELECTROCHEMISTRY), CHLORIDES, BROMIDES, SINGLE CRYSTALS, ELECTROLYTES, ELECTRODES, SILVER, VOLTAGE, OXIDATION REDUCTION REACTIONS, PHOTOGRAPHIC EMULSIONS, CHEMICAL EQUILIBRIUM, VOLUMETRIC ANALYSIS, WEST GERMANY.

Subject Categories : Physical Chemistry
      Printing and Graphic Arts

Distribution Statement : APPROVED FOR PUBLIC RELEASE