Perrin, Jean Baptiste

Paracelsus, 14, 15, 18 Parmenides, 9 Pasteur, Louis, 296 Pauli, Wolfgang, 42 Pauling, Linus, 77 Perkins, William Henry, 295 Perrin, Jean Baptiste, 56 Plante, Gaston, 186... 

Peierls Rudolph, 535 Peres Asher, 3 Pernal Katarzyna, 715 Perrin Jean-Baptiste, 722 Pestka Grzegorz, 145 Peters C. Wilbur, 722 Piecuch Piotr, 657, 659, 859 Piela Lucjan, 354, 376,... 

What exactly does it mean to have as many atoms as there are in 12 grams of C-12 The number is known as Avogadro s number, and its accepted value is 6.022 X 10. Therefore, from the definition of a mole we can say there are 6.02 X 10 atoms in a mole of C-12. The term Avogadro s number was coined by Jean Baptiste Perrin (1870-1942) who was the first to experimentally determine... 

Fig. I. Replica of plot made by Jean Baptiste Pen-in (France) in 1912 of a microscopic particle suspended in water. Tlie position of the particle was recorded at half-minute intervals. At the time, Perrin observed that only a very meager idea of the extraordinary discontinuity of the actual trajectory can be obtained in this experimental fashion...

Because radium was present in such a tiny amount, the Curies were at first unable to isolate pure samples, but had to settle for the chloride salt, RaCl2. Much to the Curies delight, they found that radium chloride glowed in the dark, just like phosphorus. The Curies took such joy in their discovery that they would entertain their scientific friends— among them Paul Langevin (1872-1946) and Jean-Baptiste Perrin (1870-1942)—by inviting them to the Curies apartment just to sit in the dark and watch their sample of radium chloride glow. 

French physicist Jean-Baptiste Perrin is born on September 30 in Lille, France. 

Jean-Baptiste Perrin receives the Nobel Prize in physics in part for his work on the study of the structure of matter. 

Sir J. J. Thomson dies on August 30 in Cambridge, England. 1942 Jean-Baptiste Perrin dies on April 17 in New York, New York. 

Experiments on sedimentation under the earth s gravitational field were carried out in 1908 by the French physicist Jean Baptiste Perrin (1870-1942), who observed under a microscope the movement of the particles of the pigment gamboge. In order to observe the sedimentation of smaller particles, such as proteins and other macromolecules, it is necessary to employ much higher fields. This is done by means of an ultracentrifuge, in which solutions are rotated at speeds up to 80 000 revolutions per minute, which produces fields up to 3 x 10 g. The development of such ultracentrifugal techniques is largely due to the Swedish physical chemist Theodor... 

This equation accurately describes the Brownian motion of microscopic particles, and was used by Jean-Baptiste Perrin in a classic series of experiments (from 1908) to estimate Avogadro s number (Aa). He was awarded the Nobel Prize for physics in 1926. 

Jean Baptiste Perrin, born Sep. 30, 1870, in LiUe France, died Apr. 17, 1942, in New York City, USA. 

A French physicist, Jean Baptiste Perrin (1870-1942), made the necessary measurements in 1908 and produced the first hard and fast estimate of the diameter of molecules and, therefore, of atoms. Since the Brownian motion was a reasonably direct... 

Jean-Baptiste Perrin (1870-1942). .. was a French physicist who worked on various subjects, for instance, on cathode rays, fluorescence, sound propagation, and the decay of radium. A major part of his scientiflc life was dedicated to colloids. His investigations on the Brownian motion of colloids by means of the previously developed ultramicroscope verified Einstein s statistic explanation of this phenomenon and thereby confirmed the atomic nature of matter. Moreover, Perrin was able to closely limit the possible range of Avogadro s number and he discovered the sedimentation-diffusion equilibrium. For his work on the discontinuous structure of matter and especially for his discovery of sedimentation equilibrium he received 1926 the Nobel Prize in Physics. 

In this period there was a great attention about the molecularity of mechanisms and of particularly interest was a debate about unimolecular reactions. The debate was that about the so called Radiative Theory (King Laidler, 1984), proposed mainly by Jean Baptiste Perrin (1870-1942), around 1917. Perrin propwsed that unimolecular processes was activated only by blackbody radiation. The hypwthesis, fallacious, continued for nearly ten years involving many and important figures as Einstein for example. Even being wrong Radiative Theory represents an interesting case study and boosted the research on different activation causes other than thermal collisions. 

Subramanyan Chandrasekhar, William A. Fowler 1926 Jean Baptiste Perrin... 

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