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Colourless diboron tetrachloride (m.p. -93 °C) is a planar molecule in the solid, (similar to dinitrogen tetroxide, but in the gas phase the structure is staggered. [4] It decomposes (disproportionates) at room temperatures to give a series of monochlorides having the general formula (BCl) n, in which n may be 8, 9, 10, or 11.
The adduct with diethyl ether, boron trifluoride diethyl etherate, or just boron trifluoride etherate, (BF 3 ·O(CH 2 CH 3) 2) is a conveniently handled liquid and consequently is widely encountered as a laboratory source of BF 3. [16] Another common adduct is the adduct with dimethyl sulfide (BF 3 ·S(CH 3) 2), which can be handled as a neat ...
[1] [2] [3] Introduced by Gilbert N. Lewis in his 1916 article The Atom and the Molecule, a Lewis structure can be drawn for any covalently bonded molecule, as well as coordination compounds. [4] Lewis structures extend the concept of the electron dot diagram by adding lines between atoms to represent shared pairs in a chemical bond.
In its pure state, boron triiodide forms colorless, otherwise reddish, shiny, air and hydrolysis-sensitive [3] crystals, which have a hexagonal crystal structure (a = 699.09 ± 0.02 pm, c = 736.42 ± 0.03 pm, space group P6 3 /m (space group no. 176)). [4] Boron triiodide is a strong Lewis acid and soluble in carbon disulfide. [2]
Boron tribromide is commercially available and is a strong Lewis acid.. It is an excellent demethylating or dealkylating agent for the cleavage of ethers, also with subsequent cyclization, often in the production of pharmaceuticals.
According to textbook knowledge, it is possible to transform a liquid continuously into a gas, without undergoing a phase transition, by heating and compressing strongly enough to go around the critical point. However, different criteria still allow to distinguish liquid-like and more gas-like states of a supercritical fluid. These criteria ...
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.
The most common Lewis bases are anions. The strength of Lewis basicity correlates with the pK a of the parent acid: acids with high pK a 's give good Lewis bases. As usual, a weaker acid has a stronger conjugate base. Examples of Lewis bases based on the general definition of electron pair donor include: simple anions, such as H − and F −