Simultaneous Knudsen- and Torsion-Effusion Measurements of the Vapor Pressures of Triphenyl Aluminum and Triphenyl Boron

Author

Steven Wayne Govorchin, Western Michigan University

Date of Award

4-1986

Degree Name

Master of Arts

Department

Chemistry

First Advisor

Dr. R. H. Anderson

Second Advisor

Dr. J. M. Kanamueller

Access Setting

Masters Thesis-Open Access

Abstract

The sublimation pressures of triphenyl aluminum and triphenyl boron have been determined from simultaneous measurements of the rate of mass effusion and torsional recoil. For triphenyl aluminum the measured vapor presures are expressed by the equations:

logio (P_k/P°) = (12.76 ± 1.25) - (8214 ± 572) (K/T)

logio (P_t/p °) = (12.83 ± 1.34) - (8206 ± 615) (K/T)

where P_k and P_t are the pressures measured by the Knudsen-effusion and torsional-recoil techniques, respectively, and p° = 101.325 kP_a. For triphenyl boron the measured vapor pressures are expressed by the equations:

log₁₀ (Pk/p°) = (9.39 ± 0.13) - (5274 ± 46) (K/T)

log₁₀ (Pt/p°) = (10.00 ± 0.07) - (5489 ± 27) (K/T)

where the same notation applies. The standard molar enthalpies and entropies, of sublimation of triphenyl aluminum monomer: Al (C₆H₅₎₃(cr) → Al (C₆H₅)₃ (g), and dissociation of the solid dimer: {Al(C₆H₅) 3}2(cr) →2Al(C₆H₅) 3(cr) are estimated. The standard molar heat of formation of gaseous triphenyl boron: △fH°m {B(C₆H₅ )3 , g, 363 K} and the mean molar bond-dissociation enthalpy (B-C₆H₅) are calculated.

Recommended Citation

Govorchin, Steven Wayne, "Simultaneous Knudsen- and Torsion-Effusion Measurements of the Vapor Pressures of Triphenyl Aluminum and Triphenyl Boron" (1986). Masters Theses. 1339.
https://scholarworks.wmich.edu/masters_theses/1339