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  2. Inorganic nonaqueous solvent - Wikipedia

    en.wikipedia.org/wiki/Inorganic_nonaqueous_solvent

    Prominent members include ammonia, hydrogen fluoride, sulfuric acid, hydrogen cyanide. Ammonia (and several amines as well) are useful for the generating solutions of highly reducing species because the N-H bond resists reduction. The chemistry of electrides and alkalides relies on amine solvents.

  3. Amine - Wikipedia

    en.wikipedia.org/wiki/Amine

    Amine. In chemistry, amines (/ ə ˈ m iː n, ˈ æ m iː n /, [1] [2] UK also / ˈ eɪ m iː n / [3]) are compounds and functional groups that contain a basic nitrogen atom with a lone pair.Formally, amines are derivatives of ammonia (NH 3 (in which the bond angle between the nitrogen and hydrogen is 107°), wherein one or more hydrogen atoms have been replaced by a substituent such as an ...

  4. Urea - Wikipedia

    en.wikipedia.org/wiki/Urea

    The structure of the molecule of urea is O=C(−NH 2) 2.The urea molecule is planar when in a solid crystal because of sp 2 hybridization of the N orbitals. [8] [9] It is non-planar with C 2 symmetry when in the gas phase [10] or in aqueous solution, [9] with C–N–H and HN–H bond angles that are intermediate between the trigonal planar angle of 120° and the tetrahedral angle of 109.5°.

  5. Hydrogen bond - Wikipedia

    en.wikipedia.org/wiki/Hydrogen_bond

    Bifurcated H-bond systems are common in alpha-helical transmembrane proteins between the backbone amide C=O of residue i as the H-bond acceptor and two H-bond donors from residue i + 4: the backbone amide NH and a side-chain hydroxyl or thiol H +. The energy preference of the bifurcated H-bond hydroxyl or thiol system is -3.4 kcal/mol or -2. ...

  6. Chemical compound - Wikipedia

    en.wikipedia.org/wiki/Chemical_compound

    A compound can be transformed into a different substance by a chemical reaction, which may involve interactions with other substances. In this process, bonds between atoms may be broken or new bonds formed or both. There are four major types of compounds, distinguished by how the constituent atoms are bonded together.

  7. Hydrazine - Wikipedia

    en.wikipedia.org/wiki/Hydrazine

    N 2 H 4 + O 2 → N 2 + 2 H 2 O. An excess of oxygen gives oxides of nitrogen, including nitrogen monoxide and nitrogen dioxide: N 2 H 4 + 2 O 2 → 2 NO + 2 H 2 O N 2 H 4 + 3 O 2 → 2 NO 2 + 2 H 2 O. The heat of combustion of hydrazine in oxygen (air) is 19.41 MJ/kg (8345 BTU/lb). [57] Hydrazine is a convenient reductant because the by ...

  8. Chemical bond - Wikipedia

    en.wikipedia.org/wiki/Chemical_bond

    Hydrogen bonds of the form A--H•••B occur when A and B are two highly electronegative atoms (usually N, O or F) such that A forms a highly polar covalent bond with H so that H has a partial positive charge, and B has a lone pair of electrons which is attracted to this partial positive charge and forms a hydrogen bond. [23]: 702 Hydrogen ...

  9. Chemical substance - Wikipedia

    en.wikipedia.org/wiki/Chemical_substance

    Pure water is an example of a chemical substance, with a constant composition of two hydrogen atoms bonded to a single oxygen atom (i.e. H 2 O). The atomic ratio of hydrogen to oxygen is always 2:1 in every molecule of water. Pure water will tend to boil near 100 °C