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Partial molar volumes

Product No: P3020501

Principle

Due to intermolecular interactions, the total volume measured when two real liquids (e.g. ethanol and water) are mixed deviates from the total volume calculated from the individual volumes of the two liquids (volume contraction). To describe this non-ideal behaviour in the mixing phase, one defines partial molar quantities which are dependent on the composition of the system . The values of these can be experimentally determined.

Tasks

Measure the densities of different ethanol-water mixtures of specified composition at 20°C with pycnometers.
Calculate the real volumes and the mean molar mixing volumes of the investigated ethanol-water mixtures and also the partial molar volumes of each liquid for selected compositions.
Compare them with the molar volumes of the pure substances at 20°C.

What you can learn about

Principles of thermodynamics
Ideal and non-ideal behaviour of gases and liquids
Volume contraction
Molar and partial molar quantities

Materiallist (Excerpt)	Product	Amount
Set of Precision Balance Sartorius CPA 623S and measure software, 230 V	49224-88	1
Immersion thermostat Alpha A, 230 V	08493-93	1
Bath for thermostat, Makrolon	08487-02	1
External circulation set for thermostat Alpha A	08493-02	1
Ethyl alcohol, absolute 500 ml	30008-50	1
Pyknometer, calibrated, 25ml	03023-00	9
Water, distilled 5 l	31246-81	1
Universal clamp	37715-00	4
Pasteur pipettes, 250 pcs	36590-00	1
Support rod, stainless steel, 500 mm	02032-00	2
Right angle clamp	37697-00	5
Rubber caps, 10 pcs	39275-03	1
Glass beaker DURAN®, tall, 50 ml	36001-00	2
Funnel, glass, top dia. 55 mm	34457-00	9
Bottle,nar.mouth,100ml,clear,p.st	41101-01	9
Wash bottle, plastic, 500 ml	33931-00	1
Rubber tubing, i.d. 6 mm	39282-00	3
Hose clip, diam. 8-16 mm, 1 pc.	40996-02	4
Laboratory Experiments Physics, Chemistry, Biology andApplied Sciences, CD-ROM, incl. operating manuals	16502-42	1