THERMODYNAMIC PROPERTIES OF ZIRCONIUM AND HAFNIUM HALIDES. PART II: HEAT OF FORMATION OF ZRCL3 QUANTITATIVE DIFFERENTIAL THERMAL ANALYSIS OF DECOMPOSITION REACTIONS.
Abstract
Modifications to a solution calorimeter are described and results given for the performance of the calorimeter in determining the enthalpy of solution of THAM(Tris(Hydroxymethyl)amino- methane) in 0.2 N HCL. The enthalpy of solution of ZrCl4(s) in 0.2 N HCl and the enthalpy of reaction of ZrCl3(s) with 0.2 N HCl have been determined. From these and auxiliary data, the enthalpy of formation at 298.15 K of ZrCl3(s) is found to be -185.2 + or - 2.5 kcal/mole, and of ZrCl2(s), -130.2 + or - 5.0 kcal/mole. The approach to quantitative differential thermal analysis (QDTA) developed by Speros and Woodhouse has been tested for applicability to disproportionation reactions by studying the decomposition of lead and zinc carbonates; the results are in reasonable agreement with data obtained by other techniques. QDTA of the ZrCl3 disproportionation has been attempted under several conditions, but has so far been unsuccessful, primarily because of the increased reactivity of ZrCl3 with water vapor at elevated temperatures. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 1967
- Accession Number
- AD0815472
Entities
People
- Robert D. Freeman
Organizations
- Oklahoma State University–Stillwater