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Diphosphorus Tetrafluoride
Diphosphorus tetrafluoride is a gaseous compound of phosphorus and fluorine with formula P2F4. Two fluorine atoms are connected to each phosphorus atom, and there is a bond between the two phosphorus atoms. Phosphorus can be considered to have oxidation state +2, as indicated by the name phosphorus difluoride. Production Diphosphorus tetrafluoride was discovered in 1966 by Max Lustig, John K. Ruff and Charles B. Colburn at the Redstone Research Laboratories. The initial synthesis reacted phosphorus iododifluoride with mercury at room temperature. 2PF2I +2Hg → P2F4 + Hg2I2 Properties The P-P bond in diphosphorus tetrafluoride is much stronger than the corresponding N-N bond in dinitrogen tetrafluoride which easily breaks into nitrogen difluoride. The infrared spectrum has absorption at 842 cm−1, 830 cm−1, 820 cm−1, and weaker at 408 cm−1 and 356 cm−1. The molecule has C2h symmetry. Reactions Under ultraviolet light diphosphorus tetraf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinitrogen Tetrafluoride
Tetrafluorohydrazine or perfluorohydrazine, , is a colourless, reactive inorganic gas. It is a fluorinated analog of hydrazine. It is a highly hazardous chemical that explodes in the presence of organic materials. Tetrafluorohydrazine is manufactured from nitrogen trifluoride using an iron catalyst or iron(II) fluoride. It is used in some chemical syntheses, as a precursor or a catalyst. Tetrafluorohydrazine was considered for use as a high-energy liquid oxidizer in some never-flown rocket fuel formulas in 1959. Properties Tetrafluorohydrazine is in equilibrium with its radical monomer nitrogen difluoride. : N2F4 2 NF2• At room temperature N2F4 is mostly associated with only 0.7% in the form of NF2 at 5mm Hg pressure. When the temperature rises to 225 °C, it mostly dissociates with 99% in the form of NF2. molecule dimensions and angles The energy needed to break the N-N bond in N2F4 is 20.8 kcal/mol, with an entropy change of 38.6 eu. For comparison, the dis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxidation State
In chemistry, the oxidation state, or oxidation number, is the hypothetical charge of an atom if all of its bonds to different atoms were fully ionic. It describes the degree of oxidation (loss of electrons) of an atom in a chemical compound. Conceptually, the oxidation state may be positive, negative or zero. While fully ionic bonds are not found in nature, many bonds exhibit strong ionicity, making oxidation state a useful predictor of charge. The oxidation state of an atom does not represent the "real" formal charge on that atom, or any other actual atomic property. This is particularly true of high oxidation states, where the ionization energy required to produce a multiply positive ion is far greater than the energies available in chemical reactions. Additionally, the oxidation states of atoms in a given compound may vary depending on the choice of electronegativity scale used in their calculation. Thus, the oxidation state of an atom in a compound is purely a formalism. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diborane
Diborane(6), generally known as diborane, is the chemical compound with the formula B2H6. It is a toxic, colorless, and pyrophoric gas with a repulsively sweet odor. Diborane is a key boron compound with a variety of applications. It has attracted wide attention for its electronic structure. Several of its derivatives are useful reagents. Structure and bonding The structure of diborane has D2h symmetry. Four hydrides are terminal, while two bridge between the boron centers. The lengths of the B–Hbridge bonds and the B–Hterminal bonds are 1.33 and 1.19 Å respectively. This difference in bond lengths reflects the difference in their strengths, the B–Hbridge bonds being relatively weaker. The weakness of the B–Hbridge compared to B–Hterminal bonds is indicated by their vibrational signatures in the infrared spectrum, being ≈2100 and 2500 cm−1 respectively. The model determined by molecular orbital theory describes the bonds between boron and the termina ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkene
In organic chemistry, an alkene is a hydrocarbon containing a carbon–carbon double bond. Alkene is often used as synonym of olefin, that is, any hydrocarbon containing one or more double bonds.H. Stephen Stoker (2015): General, Organic, and Biological Chemistry'. 1232 pages. Two general types of monoalkenes are distinguished: terminal and internal. Also called α-olefins, terminal alkenes are more useful. However, the International Union of Pure and Applied Chemistry (IUPAC) recommends using the name "alkene" only for acyclic hydrocarbons with just one double bond; alkadiene, alkatriene, etc., or polyene for acyclic hydrocarbons with two or more double bonds; cycloalkene, cycloalkadiene, etc. for cyclic ones; and "olefin" for the general class – cyclic or acyclic, with one or more double bonds. Acyclic alkenes, with only one double bond and no other functional groups (also known as mono-enes) form a homologous series of hydrocarbons with the general formula with '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alkyne
\ce \ce Acetylene \ce \ce \ce Propyne \ce \ce \ce \ce 1-Butyne In organic chemistry, an alkyne is an unsaturated hydrocarbon containing at least one carbon—carbon triple bond. The simplest acyclic alkynes with only one triple bond and no other functional groups form a homologous series with the general chemical formula . Alkynes are traditionally known as acetylenes, although the name ''acetylene'' also refers specifically to , known formally as ethyne using IUPAC nomenclature. Like other hydrocarbons, alkynes are generally hydrophobic. Structure and bonding In acetylene, the H–C≡C bond angles are 180°. By virtue of this bond angle, alkynes are rod-like. Correspondingly, cyclic alkynes are rare. Benzyne cannot be isolated. The C≡C bond distance of 121 picometers is much shorter than the C=C distance in alkenes (134 pm) or the C–C bond in alkanes (153 pm). : The triple bond is very strong with a bond strength of 839 kJ/mol. The sigma bond contribute ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitrogen Difluoride
Nitrogen difluoride, also known as difluoroamino, is a reactive radical molecule with formula . This small molecule is in equilibrium with its dimer dinitrogen tetrafluoride. : As the temperature increases the proportion of increases. The molecule is unusual in that it has an odd number of electrons, yet is stable enough to study experimentally. Properties The energy needed to break the N–N bond in is , with an entropy change of 38.6 eu. molecule dimensions and angles For comparison, the dissociation energy of the N–N bond is in , in , and in . The enthalpy of formation of (Δ''H''f) is . At room temperature is mostly associated with only 0.7% in the form of at pressure. When the temperature rises to 225 °C, it mostly dissociates with 99% in the form of . In , the N–F bond length is 1.3494 Å and the angle subtended at F–N–F is 103.33°. In the infrared spectrum the N–F bond in has a symmetrical stretching frequency of 1075 cm∠... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phosphorus Iododifluoride
Phosphorus is a chemical element with the symbol P and atomic number 15. Elemental phosphorus exists in two major forms, white phosphorus and red phosphorus, but because it is highly reactive, phosphorus is never found as a free element on Earth. It has a concentration in the Earth's crust of about one gram per kilogram (compare copper at about 0.06 grams). In minerals, phosphorus generally occurs as phosphate. Elemental phosphorus was first isolated as white phosphorus in 1669. White phosphorus emits a faint glow when exposed to oxygen – hence the name, taken from Greek mythology, meaning 'light-bearer' (Latin ), referring to the "Morning Star", the planet Venus. The term ''phosphorescence'', meaning glow after illumination, derives from this property of phosphorus, although the word has since been used for a different physical process that produces a glow. The glow of phosphorus is caused by oxidation of the white (but not red) phosphorus — a process now called chemilumin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
