Tyndall phenomenon

Hydrophobic sulfur sols can also be prepared by blowing sulfur vapor into cold water where it immediately condenses [17]. After filtration these sols are polydisperse, exhibit a strong Tyndall phenomenon, and can be kept for two to six weeks at 20 °C before the sulfur starts to settle to the bottom of the flask. The crystalline precipitate obtained in this way cannot be peptized in water but dissolves quantitatively in carbon disulfide. The sulfur content of the original but filtrated sol was between 0.01 and 0.08 mass % the particles are negatively charged and move in an electrical field to the anode. 

But the microscopic fat particles suspended in milk have an average diameter in the range 10-7 to 10-5 m, i.e. much larger than k of visible light. A beam of incident light is scattered rather than transmitted by a suspension of particles - a phenomenon known as the Tyndall effect. 

TYNDALL EFFECT. A phenomenon first noticed by Faraday (1857). When a powerful beam of fight is sent through a colloidal solution of... 

L. Pasteur, J. Tyndall, E. T. Chapman, P. Miquel, W. Spring, F. Schulz, etc. Air may be freed from dust particles, etc., in suspension by filtration through biscuit earthenware, asbestos, or cotton wool. When a beam of sunlight is passed through unfiltered air, it reveals a multitude of motes constantly in motion. Lucretius, in his Be natura remm (2.113, 60 b.c.), has given a very vivid description of the phenomenon. With filtered air, there is no such eflect, and J. Tyndall said that such air is optically empty. F. O. Rice showed that in a number of reactions— e.g. the oxidation of soln. of sodium arsenite or sulphite, the decomposition of hydrogen dioxide, etc.—the suspended dust in air acts as a catalytic agent. 

Small particles scatter and absorb light. This phenomenon has been used to investigate aerosol behavior extensively since Tyndall s work in the nineteenth century. In more recent years, instruments have been built to take advantage of light interactions to deduce particle size distributions. To appreciate how such devices work, we introduce certain basic principles of light interaction with airborne material. 

Unlike a true solution, colloidal suspensions will scatter light, a phenomenon known as the Tyndall effect. The beam of light in a smoke filled theatre is visible due to the Tyndall effect. 

The Tyndall Effect 14-17 The Adsorption Phenomenon 14-18 Llydrophilic and Hydrophobic Colloids... 

Recognize and describe colloids the Tyndall effect, the adsorption phenomenon, hydrophilic and hydrophobic colloids... 

This phenomenon was subsequently investigated by Tyndall and is known as the... 

Turbidity in a liquid results from an optical phenomenon known as the Tyndall effect, caused by the presence of particles in suspension that deflect light from its normal path. The measurement of clarity is, therefore, related to estimations of turbidity (Section 9.1.2), depending on the number and size of particles in suspension. Wine may be clarifled in the short term by eliminating these particles. However, the effect is not necessarily... 

The phenomenon was further studied by Tyndall and now bears his name, the Tyndall effect [7]. 

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