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Rubidium is a chemical element; it has symbol Rb and atomic number 37. It is a very soft, whitish-grey solid in the alkali metal group, similar to potassium and caesium. [9] Rubidium is the first alkali metal in the group to have a density higher than water.
Prepared and isolated from urine, it was the first element whose discovery date and discoverer are recorded. [53] Its name first appears in print in the work of Georg Kaspar Kirchmayer in 1676. Recognised as an element by Lavoisier. [1] 1 Hydrogen: 1671 R. Boyle: 1671 R. Boyle Robert Boyle produced it by reacting iron filings with dilute acid.
Robert Wilhelm Eberhard Bunsen (German:; 30 March 1811 [a] – 16 August 1899) was a German chemist.He investigated emission spectra of heated elements, and discovered caesium (in 1860) and rubidium (in 1861) with the physicist Gustav Kirchhoff. [11]
1924: Edwin Hubble: the discovery that the Milky Way is just one of many galaxies; 1925: Erwin Schrödinger: Schrödinger equation (Quantum mechanics) 1925: Cecilia Payne-Gaposchkin: Discovery of the composition of the Sun and that hydrogen is the most abundant element in the Universe; 1927: Werner Heisenberg: Uncertainty principle (Quantum ...
An image from John Dalton's A New System of Chemical Philosophy, the first modern explanation of atomic theory.. This timeline of chemistry lists important works, discoveries, ideas, inventions, and experiments that significantly changed humanity's understanding of the modern science known as chemistry, defined as the scientific study of the composition of matter and of its interactions.
Many cultures throughout history have speculated on the nature of the mind, heart, soul, spirit, brain, etc. For instance, in Ancient Egypt, the Edwin Smith Papyrus contains an early description of the brain, and some speculations on its functions (described in a medical/surgical context) and the descriptions could be related to Imhotep who was the first Egyptian physician who anatomized and ...
The rubidium–strontium dating method (Rb–Sr) is a radiometric dating technique, used by scientists to determine the age of rocks and minerals from their content of specific isotopes of rubidium (87 Rb) and strontium (87 Sr, 86 Sr). One of the two naturally occurring isotopes of rubidium, 87 Rb, decays to 87 Sr with a half-life of 49.
Psychology is the scientific study of mind and behavior. [1] [2] Its subject matter includes the behavior of humans and nonhumans, both conscious and unconscious phenomena, and mental processes such as thoughts, feelings, and motives. Psychology is an academic discipline of immense scope, crossing the boundaries between the natural and social ...