Article,
Vapor Pressure and Heat of Sublimation of Rhenium
JOURNAL OF RESEARCH of the National Bureau of Standards �A. Physics and Chemistry, (1966)
Abstract
The vapor pressure of rhenium was measured by the Langmuir method
in the temperature range
2350�3050 �K using a vacuum microbalance. The least squares line through
the four series of data
points is 4.5756 log P(atm) = 32.26� 180700/77. Least squares lines
for each of the four series yield
heats and entropies of sublimation higher than the corresponding third
law values. The vapor pressure
equation based on the average heat and entropy is, 4.5756 log P(atm)
= 33.36� 183500/7\
The selected third law heat of sublimation, AHg (298) is 185.9 kcal
mol"1. Our recommended
equation for the vapor pressure is 4.5756 log P(atm) = 31.86�180200/71
based on our mean third law
heat and tabulated values for the entropies and enthalpies.
