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Laboratory Course in Physical Chemistry for Fundamental Studies

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Laboratory Course in Physical Chemistry for Fundamental Studies CHAIR OF PHYSICAL CHEMISTRY TECHNISCHE UNIVERSITÄT MÜNCHEN Laboratory Course in Physical Chemistry for Fundamental Studies Experiments Manual The reproduction of this manual is funded by the tuition grant of the Chemistry Faculty _ © 2016 Chairs of Physical Chemistry of the Technical University of Munich 10th Edition (30th March 2020). Editing, typing and printing: Michele Piana, Karin Stecher, Alexander Ogrodnik, Sonja Uhl, Matthias Stecher and Peter Kämmerer. Chair of Technical Electrochemistry and Second Chair of Physical Chemistry Alle Rechte vorbehalten. Die Vervielfältigung auch einzelner Teile, Texte oder Bilder – mit Ausnahme der in SS 53, 54 UrhG ausdrücklich genannten Sonderfälle – gestattet das Urheberrecht nur, wenn sie mit den Lehrstühlen oder dem Praktikumsleiter vorher vereinbart wurde. Table of Contents 1 Vapour-Pressure Curve and Boiling-Point Elevation ............................................................................... 1 1.1 Context and aim of the experiment ....................................................................................................... 1 1.1.1 Important concepts to know ......................................................................................................... 1 1.1.2 Most common questions to be answered .................................................................................... 1 1.1.3 Further preparations before the experiment ................................................................................. 1 1.2 Theory .................................................................................................................................................... 2 1.2.1 Phase diagrams ............................................................................................................................ 2 1.2.2 Vapour pressure ............................................................................................................................ 2 1.2.3 Colligative properties and boiling-point elevation ......................................................................... 3 1.3 Experimental details and evaluation ...................................................................................................... 5 1.3.1 Experimental execution................................................................................................................. 5 1.3.2 Data evaluation ............................................................................................................................. 7 1.4 Applications of the experiment and its theory ....................................................................................... 8 1.5 Appendixes ............................................................................................................................................ 8 1.5.1 Derivation of the boiling-point elevation from the chemical potential ........................................... 8 1.5.2 Basic instructions to use the software .......................................................................................... 9 1.6 Literature.............................................................................................................................................. 11 2 Freezing-Point Depression ....................................................................................................................... 12 2.1 Context and aim of the experiment ..................................................................................................... 12 2.1.1 Important concepts to know ....................................................................................................... 12 2.1.2 Most common questions to be answered .................................................................................. 12 2.1.3 Further preparations before the experiment ............................................................................... 12 2.2 Theory .................................................................................................................................................. 13 2.2.1 Phase diagrams .......................................................................................................................... 13 2.2.2 Colligative properties .................................................................................................................. 13 2.2.3 Derivation of freezing-point depression from chemical potential................................................ 13 2.2.4 Supercooling of a liquid .............................................................................................................. 15 2.3 Experimental details and evaluation .................................................................................................... 15 2.3.1 Experimental execution............................................................................................................... 15 2.3.2 Data evaluation ........................................................................................................................... 17 2.4 Applications of the experiment and its theory ..................................................................................... 17 2.5 Appendixes .......................................................................................................................................... 17 2.5.1 Basic Instructions to use the software ........................................................................................ 17 2.6 Literature.............................................................................................................................................. 19 3 Joule-Thomson Effect .............................................................................................................................. 20 3.1 Context and aim of the experiment ..................................................................................................... 20 i Table of Contents 3.1.1 Important concepts to know ....................................................................................................... 20 3.1.2 Most common questions to be answered ................................................................................... 20 3.1.3 Further preparations before the experiment ............................................................................... 20 3.2 Theory ................................................................................................................................................. 21 3.2.1 Internal energy and intermolecular interactions .......................................................................... 21 3.2.2 The Joule-Thomson-Experiment ................................................................................................. 22 3.2.3 Thermodynamic analysis of the Joule-Thomson effect............................................................... 22 3.2.4 Derivation of the expansion coefficient and the Joule-Thomson coefficient .............................. 25 3.2.5 Calculation of the inversion curve using the van-der-Waals equation of state ........................... 26 3.3 Experimental details and evaluation ................................................................................................... 26 3.3.1 Experimental execution ............................................................................................................... 27 3.3.2 Data evaluation ........................................................................................................................... 28 3.4 Applications of the experiment and its theory .................................................................................... 29 3.5 Appendixes ......................................................................................................................................... 29 3.5.1 Basic instructions to use the software ........................................................................................ 29 3.5.2 Instruction for data treatment ...................................................................................................... 30 3.5.3 Van-der-Waals parameters ......................................................................................................... 32 3.5.4 Further implementations in the derivation of the Joule-Thomson coefficient for real gases ....... 32 3.5.5 Further implementations in the derivation of the inversion temperature for real gases .............. 33 3.5.6 Virial coefficient ........................................................................................................................... 34 3.6 Literature ............................................................................................................................................. 34 4 Combustion Enthalpy via Bomb Calorimetry .......................................................................................... 35 4.1 Context and aim of the experiment..................................................................................................... 35 4.1.1 Important concepts to know ....................................................................................................... 35 4.1.2 Most common questions to be answered ................................................................................... 35 4.1.3 Further preparations before the experiment ............................................................................... 35 4.2 Theory ................................................................................................................................................
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