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  2. 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°.

  3. Molecule - Wikipedia

    en.wikipedia.org/wiki/Molecule

    The simplest of molecules is the hydrogen molecule-ion, H 2 +, and the simplest of all the chemical bonds is the one-electron bond. H 2 + is composed of two positively charged protons and one negatively charged electron , which means that the Schrödinger equation for the system can be solved more easily due to the lack of electron–electron ...

  4. Ammonia - Wikipedia

    en.wikipedia.org/wiki/Ammonia

    The standard enthalpy change of combustion, ΔH° c, expressed per mole of ammonia and with condensation of the water formed, is −382.81 kJ/mol. Dinitrogen is the thermodynamic product of combustion: all nitrogen oxides are unstable with respect to N 2 and O 2, which is the principle behind the catalytic converter.

  5. Hydrate - Wikipedia

    en.wikipedia.org/wiki/Hydrate

    The notation "hydrated compound⋅n H 2 O", where n is the number of water molecules per formula unit of the salt, is commonly used to show that a salt is hydrated. The n is usually a low integer, though it is possible for fractional values to occur. For example, in a monohydrate n = 1, and in a hexahydrate n = 6.

  6. 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. ...

  7. Inorganic compound - Wikipedia

    en.wikipedia.org/wiki/Inorganic_compound

    The Inorganic Crystal Structure Database (ICSD) in its definition of "inorganic" carbon compounds, states that such compounds may contain either C-H or C-C bonds, but not both. [7] The book series Inorganic Syntheses does not define inorganic compounds. The majority of its content deals with metal complexes of organic ligands. [8]

  8. Non-covalent interaction - Wikipedia

    en.wikipedia.org/wiki/Non-covalent_interaction

    A hydrogen bond (H-bond), is a specific type of interaction that involves dipole–dipole attraction between a partially positive hydrogen atom and a highly electronegative, partially negative oxygen, nitrogen, sulfur, or fluorine atom (not covalently bound to said hydrogen atom). It is not a covalent bond, but instead is classified as a strong ...

  9. Ammonium - Wikipedia

    en.wikipedia.org/wiki/Ammonium

    After that, all four NH bonds are equivalent, being polar covalent bonds. The ion has a tetrahedral structure and is isoelectronic with methane and the borohydride anion. In terms of size, the ammonium cation ( r ionic = 175 pm) [ citation needed ] resembles the caesium cation ( r ionic = 183 pm).