Search results
Results from the WOW.Com Content Network
Thiocyanate [6] is known to be an important part in the biosynthesis of hypothiocyanite by a lactoperoxidase. [7] [8] [9] Thus the complete absence of thiocyanate or reduced thiocyanate [10] in the human body, (e.g., cystic fibrosis) is damaging to the human host defense system.
Thiocyanate complexes are not widely used commercially. Possibly the oldest application of thiocyanate complexes was the use of thiocyanate as a test for ferric ions in aqueous solution. [14] The reverse was also used: testing for the presence of thiocyanate by the addition of ferric salts. The 1:1 complex of thiocyanate and iron is deeply red.
In methyl thiocyanate, N≡C and C−S distances are 116 and 176 pm. By contrast, N=C and C=S distances are 117 and 158 pm in isothiocyanates. [7] Typical bond angles for C−S−C are 100°. [3] By contrast C−N=C in aryl isothiocyanates is 165°. Again, the thiocyanate isomers are quite different with C−S−C angle near 100°.
In terms of Lewis structures, formal charge is used in the description, comparison, and assessment of likely topological and resonance structures [7] by determining the apparent electronic charge of each atom within, based upon its electron dot structure, assuming exclusive covalency or non-polar bonding.
The formal charges computed for the remaining atoms in this Lewis structure of carbon dioxide are shown below. It is important to keep in mind that formal charges are just that – formal, in the sense that this system is a formalism. The formal charge system is just a method to keep track of all of the valence electrons that each atom brings ...
In chemistry, an ate complex is a salt formed by the reaction of a Lewis acid with a Lewis base whereby the central atom (from the Lewis acid) increases its valence and gains a negative formal charge. [1] (In this definition, the meaning of valence is equivalent to coordination number).
The esters of thiocyanic acid have the general structure R−S−C≡N, where R stands for an organyl group. Isothiocyanic acid, HNCS, is a Lewis acid whose free energy, enthalpy and entropy changes for its 1:1 association with a variety of Lewis bases in carbon tetrachloride solution at 25 °C have been reported.
For example, in the formation of an ammonium ion from ammonia and hydrogen the ammonia molecule donates a pair of electrons to the proton; [11] the identity of the electrons is lost in the ammonium ion that is formed. Nevertheless, Lewis suggested that an electron-pair donor be classified as a base and an electron-pair acceptor be classified as ...