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Vapor pressures of n-heptane determined by comparative ebulliometry



Jesus Sanchez Ochoa, Michael B. Ewing


The vapor pressures of n-heptane have been measured using comparative ebulliometry with water as the reference substance. The measurements cover the temperature and pressure range 372 K and 102 kPa to 537 K and 2621 kPa and were correlated by a Wagner type equation with a standard deviation of 16 Pa in the vapor pressure. The critical pressure was treated as an adjustable parameter and the value pc = 2734 kPa was obtained using a selected critical temperature, Tc = 540.13 K. The calculated normal boiling temperature is Tb = 371.552 K and an extrapolation to the triple point pressure at Ttp = 182.59 K predicts a pressure, ptp = 0.178 Pa.
Journal of Chemical and Engineering Data


Comparative Ebulliometry, critical point, n-heptane, normal boiling point, triple point, Vapor Pressures, Wagner equations


Sanchez Ochoa, J. and Ewing, M. (2005), Vapor pressures of n-heptane determined by comparative ebulliometry, Journal of Chemical and Engineering Data, [online], (Accessed July 23, 2024)


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Created July 12, 2005, Updated October 12, 2021