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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 +.
Bromine readily reacts with water, i.e. it undergoes hydrolysis: Br 2 + H 2 O → HOBr + HBr. This forms hypobromous acid (HOBr), and hydrobromic acid (HBr in water). The solution is called "bromine water". The hydrolysis of bromine is more favorable in the presence of base, for example sodium hydroxide: Br 2 + NaOH → NaOBr + NaBr
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.
See also: Electronegativities of the elements (data page) There are no reliable sources for Pm, Eu and Yb other than the range of 1.1–1.2; see Pauling, Linus (1960).
Group → 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18; ↓ Period 1: H 2 20.271 K (−252.879 °C) He 4.222 K (−268.928 °C) 2: Li 1603 K (1330 °C) Be 2742 K ...
A chemical element, often simply called an element, is a type of atom which has a specific number of protons in its atomic nucleus (i.e., a specific atomic number, or Z). [ 1 ] The definitive visualisation of all 118 elements is the periodic table of the elements , whose history along the principles of the periodic law was one of the founding ...
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.
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 −