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R 2 C=CR 2 + Br 2 → R 2 C(Br)−C(Br)R 2. Bromine is deeply colored but R 2 C(Br)−C(Br)R 2 is not. Thus, the consumption of bromine can often be gauged visually. Alternatively and more quantitatively, the bromine consumed by a sample can be determined by iodometry. [1] The bromine number indicates the degree of unsaturation of a sample. The ...
Bromine monofluoride in ethanol readily leads to the monobromination of the aromatic compounds PhX (para-bromination occurs for X = Me, Bu t, OMe, Br; meta-bromination occurs for the deactivating X = –CO 2 Et, –CHO, –NO 2); this is due to heterolytic fission of the Br–F bond, leading to rapid electrophilic bromination by Br +.
{{Infobox element}}; labels & notes: (Image) GENERAL PROPERTIES Name Symbol Pronunciation (data central) Alternative name(s) Allotropes Appearance <element> IN THE PERIODIC TABLE Periodic table Atomic number Standard atomic weight (data central) Element category (also header bg color) (sets header bg color, over 'series='-color) Group Period ...
The mass number (symbol A, from the German word: Atomgewicht, "atomic weight"), [1] also called atomic mass number or nucleon number, is the total number of protons and neutrons (together known as nucleons) in an atomic nucleus. It is approximately equal to the atomic (also known as isotopic) mass of the atom expressed in atomic mass units.
Bromine (35 Br) has two stable isotopes, 79 Br and 81 Br, and 35 known radioisotopes, the most stable of which is 77 Br, with a half-life of 57.036 hours.. Like the radioactive isotopes of iodine, radioisotopes of bromine, collectively radiobromine, can be used to label biomolecules for nuclear medicine; for example, the positron emitters 75 Br and 76 Br can be used for positron emission ...
The halogens (/ ˈ h æ l ə dʒ ə n, ˈ h eɪ-,-l oʊ-,-ˌ dʒ ɛ n / [1] [2] [3]) are a group in the periodic table consisting of six chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and the radioactive elements astatine (At) and tennessine (Ts), though some authors [4] would exclude tennessine as its chemistry is unknown and is theoretically expected to ...
A bromide ion is the negatively charged form (Br −) of the element bromine, a member of the halogens group on the periodic table. Most bromides are colorless. Most bromides are colorless. Bromides have many practical roles, being found in anticonvulsants, flame-retardant materials, and cell stains. [ 3 ]
Note: All measurements given are in picometers (pm). For more recent data on covalent radii see Covalent radius.Just as atomic units are given in terms of the atomic mass unit (approximately the proton mass), the physically appropriate unit of length here is the Bohr radius, which is the radius of a hydrogen atom.