Hydrazinium thiocyanate

The IR (Infrared) spectra of hydrazinium salts show an absorption peak in the region 960-980 cm, which is characteristic of z n-n of N2H5" ". The IR spectrum of hydrazinium thiocyanate is shown in Figure 2.2 as a representative of the hydrazinium salts. The z n-n characteristic of N2H5 is observed at 973 cm in addition to thiocyanate bands at around 2100 and 1400 cm (Figure 2.2a). 

Figure 2.3a shows the TG-DTA curves of N2H5SCN. The TG of hydrazinium thiocyanate shows no weight loss up to 125 °C. After this temperature it decomposes with a break at 350 °C (weight loss of about 70%). The... 

DTA shows the first endotherm at 98 °C due to melting there is some partial rearrangement of hydrazinium thiocyanate to thiosemicarbazide (confirmed by IR spectra - Figure 2.2b). As the process is dynamic there is not enough time for complete conversion. Above this temperature there is equilibrium between these two compounds. The exothermic peak at 156 °C is followed by several exotherms at 242,266,310,490,540,590 °C, and so on, as seen from the DTA curve. The exact nature of these peaks is difficult to assign as TG shows no definite steps corresponding to these temperatures. It is more probable that thiosemicarbazide and hydrazinium thiocyanate react to form a cyclic compound or linear polymeric compound. 

On heating solid N2H5SCN at 100 °C for 9 h at atmospheric pressure, the peaks due to N—N stretching disappear and peaks between 1000 and 800 cm due to the CS group of thiosemicarbazide are observed (2.6). It is known that hydrazinium thiocyanate rearranges to thiosemicarbazide similar to the classical rearrangement of ammonium cyanate to urea [8] ... 

The conversion yield of hydrazinium thiocyanate into thiosemicarba-zide is about 40% when the isomerization is carried out in solution. It is well known that the conversion yield of N2H5SCN into thiosemicarbazide is 74.8% in the solid state. However, when it is heated isothermally the conversion into thiosemicarbazide is almost 100%. The IR spectrum of the converted sample is superimposable with that of a commercial thiosemicarbazide sample (Figure 2.2b and c). 

The synthesis of metal hydrazine complexes with thiocyanate or isothiocyanate as anions can be carried out by the following methods [8]. In the first case, stoichiometric quantities of metal(II) salts like chlorides or sulfates of Mn, Fe, Co, Ni, Zn, and Cd in an alcohol-water mixture (1 1 by volume) are added to hydrazinium thiocyanate. The latter is metathet-ically formed by the reaction of NH4SCN -I- N2H4 H2O (1 1 mole ratio) (Chapter 2) ... 

In another method, metal powders free from an oxide film are added directly to a solution of N2H5SCN in hydrazine hydrate. Owing to the high acidic nature of hydrazinium thiocyanate formed in situ, the metal powders dissolve instantaneously with the liberation of hydrogen gas, forming metal isothiocyanate hydrazines ... 

Although thiocyanate with neutral amines (bases) has been investigated intensively with transition metals, knowledge of the respective thiocyanates with cationic amines is very limited and, in particular, with the hydrazinium cation is almost unknown. The absence of reports on the hydrazinium metal complexes of thiocyanates is not surprising as the usual method of preparation from aqueous solutions of the metal thiocyanates and hydrazinium thiocyanate always yields metal thiocyanate hydrazines. The first examples in which the hydrazinium cations are coordinated to the metal in the cis... 

The reaction between metal thiocyanates and hydrazinium thiocyanates cannot be used to prepare hydrazinium metal thiocyanate complexes. Consequently, an alternate method is employed, namely, the decomposition of hydrazinium metal hydrazine carboxylates with dilute thiocyanic acid (<5%) [27,28]. Hydrazinium metal hydrazine carboxylates complexes N2H5M(N2H3C00)3 H20, where M = Co and Ni, are prepared from metal nitrates, sulfates, or chlorides and hydrazine hydrate saturated with carbon dioxide. The dilute thiocyanic acid is prepared by adding barium thiocyanate trihydrate to dilute sulfuric acid. 

Hydrazinium Thiocyanate as Analytical Reagent for the Quantitative Estimation of Copper... 

The solution should be free from the following, which either interfere or lead to an unsatisfactory deposit silver, mercury, bismuth, selenium, tellurium, arsenic, antimony, tin, molybdenum, gold and the platinum metals, thiocyanate, chloride, oxidising agents such as oxides of nitrogen, or excessive amounts of iron(III), nitrate or nitric acid. Chloride ion is avoided because Cu( I) is stabilised as a chloro-complex and remains in solution to be re-oxidised at the anode unless hydrazinium chloride is added as depolariser. 

MERCURY(n) NITRATE (10045-94-0, anhydrous 7783-34-8, monohydrate) Hg(N03)2 H,0 Noncombustible solid. Light sensitive. A powerful oxidizer accelerates the burning of combustible materials. Violent reaction, or may form explosive materials, with reducing agents, including hydrides, nitrides, phosphorus, stannous chloride, and sulfides alkyl esters (forms explosive alkyl nitrates) combustible materials (especially if finely divided), phosphinic acid, hypophosphoric acid, metal powders petroleiun hydrocarbons. Forms heat- and/or shock-sensitive compounds with acetylene (forms explosive mercmy acetylide), ethanol and other alcohols (may form explosive mercury fulminates), ferrocene, isobutene, phosphine gas (forms heat- and shock-sensitive precipitate) potassiiun cyanide, sulfur. Incompatible with strong acids, acetic anhydride, ammonia, ammonium hexacyanofenate(II), organic azides, citric acid, hydrazinium perchlorate, isopropyl chlorocarbonate, nitrosyl perchlorate, sodium thiosulfate, sulfamic acid, thiocyanates, hydrozoic acid, methyl isocyanoacetate, sodium peroxyborate, trinitrobenzoic acid, urea nitrate. Aqueous solution corrodes metals. 

HEXAHYDRATE (10377-60-3) A powerful oxidizer. Reacts violently with dimethyl-formamide, reducing agents, combustible materials, fuels, organic substances, metal powders, potassium hexanitrocobalite(III) (C.I. pigment yellow), sodium acetylide, and easily oxidizable matter. Incompatible with aluminum, ammonium hexacyanoferrate(II), tert-butylhydroperoxide, citric acid, ethanol, ferrocyanides, hydrazinium perchlorate, isopropyl chlorocarbonate, metal phosphinates, nitrosyl perchlorate, organic azides, phosphorus, sodium thiosulfate, sulfamic acid, thiocyanates, tin(II) fluoride, and many other substances. 

NITRATO de ZINC (Spanish) (7779-88-6) Noncombustible, but will enhance the combustibility of other materials. Many chemical reactions can cause fire and explosions. A strong oxidizer. Violent reaction with reducing agents, strong oxidizers, combustible materials, organic substances, metallic powders, acetic anhydride, /err-butylhydroperoxide, carbon, di-methylformamide, metal cyanides, metal sulfides, phosphorus, sodium acetylide, sulfur, thiocyanates. Incompatible with amines, ammonium hexacyanoferrate(II), boranes, cyanides, citric acid, esters, hydrazinium perchlorate, isopropyl chlorocarbonate, nitrosyl perchlorate, organic azides, organic bases, sodium thiosulfate, sulfamic acid. Attacks metals in the presence of moisture. 

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