AbstractsChemistry

The effect of spontaneous crystallization of some inorganic compounds at the critical temperature of their solvents

by John W. (John William) Buttrey




Institution: Missouri University of Science and Technology
Department:
Year: 1948
Record ID: 1514419
Full text PDF: http://hdl.handle.net/10355/26231


Abstract

"For many years the phenomena which occur at the critical temperature of liquids have been investigated. And since 1912, when Laue and other discovered that a beam of x-rays could be made to yield a diffraction pattern by passing it through a crystal, scientists have been attempting to change the x-ray pattern for various crystals by somehow changing the arrangement of the atoms in the crystal lattice. Harvalik has already shown that crystallization occurs when a solvent reaches the critical point and his work indicates that under these conditions of crystallization there is a change in the crystal pattern. The work embodied in this dissertation is an extension of the work of Dr. Harvalik, mentioned above, incorporating some inorganic salts previously not investigated. In this research problem four water soluble salts are crystallized at the critical temperature of water. Two of the salts, sodium chloride and barium nitrate, are in the cubic system; barium chloride is in the monoclinic system; and sodium sulfate is in the rhombic system. Complete intensity calculations have been made for sodium chloride as well as graphs showing the crystal patterns of the salt in the commercial state and the crystal patterns after crystallization at the critical temperature. The intensity calculations have been omitted for the other crystals, but the graphs showing the crystal patterns are included for the salts. An attempt was made to demonstrate that under these conditions crystal patterns develop which are slightly different from those obtained under ordinary conditions" – Introduction, p. 1-2.