Lecture experiments

Since he sometimes had more than five hundred students, it was necessary for him to perform the lecture experiments on a very large scale (54). 

The isolation of vanadium can be effected on a very small scale, suitable as a lecture experiment, by passing an electric current through a platinum wire filament immersed in vanadium oxytrichloride, VOCl3, either iti vacuo or in an atmosphere of hydrogen.10 The metal is obtained as a smooth, silver-grey deposit. 

A pretty lecture experiment consists m admitting oxygen to a large glass bell jar filled with nitric oxide, and containing the bulb of an air thermoseope. As the brown fumes are formed, the thermoscope registers a sharp rise in temperature. 

A pretty lecture experiment consists m suspending a spiral of platinum wire in a beaker over some methyl alcohol. The latter is ignited, and when the spiral has become warm a card, punctured with small holes, is laid over the top of the beaker. This extinguishes the flames, but sufficient air enters to allow some of the alcohol to hum oil the surface of the platinum, which glows at red heat. 

Young T (1804) The Bakerian lecture. Experiments and calculations relative to physical optics. Phil Trans R Soc Lond 94 1-16... 

When iron wire is strongly heated in an atmosphere of oxygen it burns with a brilliant flame. A pleasing lecture experiment consists in holding a bunch of fine iron wire in the upper part of a Bunsen flame and allowing a jet of oxygen from a gas cylinder to impinge upon the whole. 

This is mad the basis of an effective lecture experiment. See Newth, Chemical Lecture Experiments (Longmans), 1910, No. 380. 

An interesting lecture experiment to illustrate suppression of hydrolysis of ferric chloride under certain conditions consists in diluting a solution of the salt until it is practically colourless. Concentrated hydrochloric acid is now added, and the solution assumes a yellow colour, characteristic of the un-ionised FeCl3-molecule.2 The addition of glycerol to a solution likewise intensifies the colour, and this is attributed to diminished dissociation consequent upon the introduction of a substance possessing a lower dielectric constant. 

Dieleren, H. M. L. Schoutetent, A. P. H. Removal of Crude Oil From Marine Surfaces— An Ecological Lecture Experiment, J. Chem. Educ. 1972,49, 19-20. 

Many lecture experiments have been proposed for demonstrating the laws of chemical kinetics. Nevertheless, they fail to meet those criteria one can justifiably impose for lecture-demonstration purposes from the standpoint of simplicity, transparency, impressiveness, and reliability. With respect to impressiveness and clarity of the phenomenon, as well as the element of surprise, the Landolt experiment stands out in first place. Conducted in the usual way, however, it is necessarily deprived of its simplicity and transparency. 

Test for the Presence of a Free Add. Dissolve chloride of silver in just sufficient ammonia to make a clear solution. If a littlo of tho test bo added to ordinary spring water, tho carbonic acid present in the latter will neutralize the ammonia and precipitate the chloride. The above forms a good lecture experiment, the test being a very delicate one. 

T. Young, The bakerian lecture experiments and calculations relative to physical optics. Philos. Trans. R. Soc. Lond. 94, 1-16 (1804). ISSN 02610523. http //www.jstor.org/stable/107135... 

In i860 Hofmann adopted the new atomic weights of Gerhardt and Cannizzaro and used them in his lectures. He published over fifty lecture experiments, many for demonstrating the volumetric composition of gases leading to the molecular formulae. His vapour density method was an improvement of Gay-Lussac s (see p. 82). He devised a gas furnace for combustion analysis. ... 

Many colloids other than gold can be removed from solution by the same method. As a lecture experiment the author uses the adsorption of molybdenum blue by animal charcoal. The dark blue liquid becomes quite colorless on shaking and filtering. As in many other cases the adsorption is quantitative and irreversible. ... 

Wk8 Ch3 Student lectures experiments Wk9 Ch4 Terpenoids WklO Ch4 Student lectures experiments Wkll Ch5 Carbohydrates Wkl2 Ch5 Student lectures experiment Wkl3 Ch6 Lignins experiments Wkl4 Ch7 Self-assembly experiments wrap up. Wkl5 Final exam... 

Ogawa, T. Haworth Memorial Lecture Experiments Directed Towards Glycoconjugate Synthesis, CSR 1994,23,397-407... 

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