REACTIONS RESPONSIBLE FOR HIGH pH OF Na‐SATURATED SOILS AND CLAYS

Abstract

Summary Hydrolysis, defined as double decomposition between Na‐adsorbent and water, occurred to extremely limited extent in suspensions of Na or Na‐Ca smectites, soil, or Dowex‐50. High pH, near 10 or above, occurred only when CaCO 3 was present. Concentrations of Na were from 1–5 me/l in systems containing CaCO 3 , With Na or Na‐Ca Dowex‐5o and CaCO 3 , in CO 2 ‐free water or NaCl solution, pH and concentrations of Na in solution‐phase were predictable from Na‐Ca exchange coefficients, CaCO 3 , solubility product, and ionization constants of H 2 CO 3 .