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(Br 2) 265.8 K (−7.2 °C ... it has symbol Br and atomic number 35. It is a volatile red-brown liquid at room temperature that evaporates readily to form a ...
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 ...
The configurations of the elements in this table are written starting with [Og] because oganesson is expected to be the last prior element with a closed-shell (inert gas) configuration, 1s 2 2s 2 2p 6 3s 2 3p 6 3d 10 4s 2 4p 6 4d 10 4f 14 5s 2 5p 6 5d 10 5f 14 6s 2 6p 6 6d 10 7s 2 7p 6. Similarly, the [172] in the configurations for elements ...
Each distinct atomic number therefore corresponds to a class of atom: these classes are called the chemical elements. [5] The chemical elements are what the periodic table classifies and organizes. Hydrogen is the element with atomic number 1; helium, atomic number 2; lithium, atomic number 3; and so on.
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 ...
Although dibromine is a strong oxidising agent with a high first ionisation energy, very strong oxidisers such as peroxydisulfuryl fluoride (S 2 O 6 F 2) can oxidise it to form the cherry-red Br + 2 cation. A few other bromine cations are known, namely the brown Br + 3 and dark brown Br + 5. [8] The tribromide anion, Br −
Electron affinity can be defined in two equivalent ways. First, as the energy that is released by adding an electron to an isolated gaseous atom. The second (reverse) definition is that electron affinity is the energy required to remove an electron from a singly charged gaseous negative ion.