Thermodynamic properties of solid and liquid ethylbenzene from 0 to 300 degrees K

Abstract

The following properties of a sample of high purity ethylbenzene were measured: (1) Specific heat of solid and liquid from 15 0 to 300 0 Ie; (2) triple-point temperature (-95.005 ±0.01O° C for pure ethyl benzene) ; (3) heat of fusion (86.47 into i g-1); (4) heat of vaporization at 294 0 Ie (400.15 into j g-1); and (5) vapor pressure from 273 0 to 296 0 Ie. With these experimental data, the enthalpy and entropy of the solid and of the liquid in the range 0 0 to 300 0 Ie were calculated. CONTENTS Pag e I. Introduction ______ ____ ___ _____ _______ ____________ ___________ __ 501 II. Purification of the sample_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 502 III. Calorimetric measurements _____ _________ _______ __ ______ _____ ____ 502 1. Apparatus ________________ __ __ __________________ _______ _ 502 2. Specific heat of solid and liquid ___ _____________ ________ ___ 503 3. Heat of fusion and triple-point temperature ___ _______ ______ _ 505 4. Heat of vaporization ____ ___ ____ _______ _______ ____ ___ ___ __ 506 IV. Vapor pressure ___________ _________ ___ __ _______ ____ ______ ______ 506 1. Apparatus and method ___ _______ ____ _______ _____ _________ 506 2. Results ____ ______ ___ ______ __________ ____ ____________ ___ 508 V. Properties derivable from the calorimetric and vapor-pressure data __ _ 509 1. Entropy and enthalpy of solid and liquid ____ __ _____ _______ _ 509 2. Heat of vaporization calculated from the vapor-pressure equation ______ _____ ____ ____ ____ __ ________________ _______ 509 VI. Estimate of errors_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 509 1. Calorimetric measurements_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 509 2. Vapor pressure ___ __ _____________ __ ______ ____ ____ ________ 510 3. Calculated values of entropy and enthalpy _ ____ ___________ _ 510 VII. Comparisons with the results of other observers _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 510 VIII. References __ _____ _______ ___ ___ ______________ ____ __ ______ ______ 512