Manov, George G.
Chemist, National Bureau of Standards, Washington, D. C.,
Pages: 10 Published: Jan 1947
For the purpose of calibrating pH meters such as the hydrogen-calomel and the glass-calomel type, it is necessary to have on hand a number of buffer solutions of certified pH value covering the ranges of temperature and pH over which it is desired to work. Of the large number of compounds both organic and inorganic known to the chemist, comparatively few, however, have the requisite properties, such as uniformity and reproducibility of composition, freedom from deliquescence or efflorescence, ease of preparation and purification, and good buffer capacity, which would make them acceptable as buffer materials. In the past thirty years the concept of the term pH underwent a change from that of the simple definition of
Paper ID: STP47876S