Some Physical Properties of Monochloro‐, Dichloro‐, and Monobromoacetic Acids at 1 Atmosphere

Abstract

Monochloro-, dichloro-, and nionobromoacetic acids (99.8 mole percent or better) have been prepared. The following physical properties have been determined: melting point (monobromo and dichloro acids), dielectric constants of liquid and solid (monochloro and dichloro), specific heat of solid (monobronio and dichloro), and heat of fusion (dichloro). Thermal analysis of solutions of the monobromo and dichloro acids with each other, with monochloro acid, and with water was used to obtain the phase diagrams. Three polymorphic forms of nionochloroacetic acid were found at normal pressures; no polymorphs were found for the dichloro and monobromo acids. Formation of a continuous series of solid solutions between monobromoacetic acid and the metastable p-form of monochlorcacetic acid suggests that this metastable form and the monobromo acid have the same crystal structure.