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Standard atomic weight A r °(Br) [79.901, ... Bromine is a chemical element; it has symbol Br and atomic number 35.
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 ...
For example, bromine has only two stable isotopes, 79 Br and 81 Br, naturally present in approximately equal fractions, which leads to the standard atomic mass of bromine close to 80 (79.904 g/mol), [10] even though the isotope 80 Br with such mass is unstable.
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. Bromides have many practical roles, being found in anticonvulsants, flame-retardant materials, and cell stains. [3]
The periodic table, also known as the periodic table of the elements, is an ordered arrangement of the chemical elements into rows (" periods ") and columns (" groups "). It is an icon of chemistry and is widely used in physics and other sciences. It is a depiction of the periodic law, which states that when the elements are arranged in order ...
A total of 33 isotopes of bromine have been discovered, with atomic masses ranging from 66 to 98. There is one stable and naturally occurring isotope of iodine , iodine-127 . However, there are trace amounts in nature of the radioactive isotope iodine-129 , which occurs via spallation and from the radioactive decay of uranium in ores.
The atomic mass (ma or m) is the mass of an atom. Although the SI unit of mass is the kilogram (symbol: kg), atomic mass is often expressed in the non-SI unit dalton (symbol: Da) – equivalently, unified atomic mass unit (u). 1 Da is defined as 1⁄12 of the mass of a free carbon-12 atom at rest in its ground state. [1]
Atomic radius. Diagram of a helium atom, showing the electron probability density as shades of gray. The atomic radius of a chemical element is a measure of the size of its atom, usually the mean or typical distance from the center of the nucleus to the outermost isolated electron. Since the boundary is not a well-defined physical entity, there ...