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Quaternary ammonium cation. The R groups may be the same or different alkyl or aryl groups. Also, the R groups may be connected. In organic chemistry, quaternary ammonium cations, also known as quats, are positively-charged polyatomic ions of the structure [NR 4] +, where R is an alkyl group, an aryl group [1] or organyl group.
In chemistry, a quaternary compound is a compound consisting of exactly four chemical elements. In another use of the term in organic chemistry , a quaternary compound is or has a cation consisting of a central positively charged atom with four substituents, especially organic ( alkyl and aryl ) groups, discounting hydrogen atoms.
Ammonium is a modified form of ammonia that has an extra hydrogen atom. It is a positively charged ( cationic ) molecular ion with the chemical formula NH + 4 or [NH 4 ] + . It is formed by the addition of a proton (a hydrogen nucleus) to ammonia ( NH 3 ).
Quaternary ammonium compounds are positively charged polyatomic ions of the structure NR 4 + with R being alkyl or aryl groups. The R groups may also be connected. The R groups may also be connected. Wikimedia Commons has media related to Quaternary ammonium compounds .
Ammonia fungi (9 P) H. Hydroxylammonium compounds (3 P) M. Methylammonium compounds (9 P) Q. Quaternary ammonium compounds (7 C, 251 P) Pages in category "Ammonium ...
Like other quaternary ammonium cations, TPA is prepared by the alkylation of the corresponding ammonia analogue, tripropylamine. Treatment of the amine with a primary propyl halide such as n-bromopropane yields the corresponding TPA halide salt in a Menshutkin reaction: (C 3 H 7) 3 N + C 3 H 7 Br → (C 3 H 7) 4 N + Br −
Tetramethylammonium hydroxide (TMAH or TMAOH) is a quaternary ammonium salt with molecular formula N(CH 3) 4 + OH −. It is commonly encountered in form of concentrated solutions in water or methanol. TMAH in solid state and its aqueous solutions are all colorless, but may be yellowish if impure.
Theories of chemical structure were first developed by August Kekulé, Archibald Scott Couper, and Aleksandr Butlerov, among others, from about 1858. [4] These theories were first to state that chemical compounds are not a random cluster of atoms and functional groups, but rather had a definite order defined by the valency of the atoms composing the molecule, giving the molecules a three ...