Ammonia/hydrazine

Volatile hydrides, except those of Periodic Group VII and of oxygen and nitrogen, are named by citing the root name of the element (penultimate consonant and Latin affixes. Sec. 3.1.2.2) followed by the suffix -ane. Exceptions are water, ammonia, hydrazine, phosphine, arsine, stibine, and bismuthine. 

Ammonia, hydrazine, nitrites, and azides ate oxidized by bromine. Nitrogen is often a product of such reactions. 

In the total alkalinity column, zero alkalinity refers to hydroxide ion (i.e., 2P-M). There is always some alkalinity produced by ammonia, hydrazine, morpholine, or other bases. 

There are various passivation chemistries commonly available. Some are better than others, but the strongest oxidizers produce the most effective passivation. The addition of air to the boiler during passivation improves weaker passivators such as ammonia/hydrazine. Chemistries include ... 

Ammonia/hydrazine passivator An alkaline hydrazine solution (pH over 9.0, 0.5% N2H2) provides a useful passivator. If there are concerns over the use of hydrazine, diethylhydroxylamine (DEHA), erythorbate, or carbohydrazide may be substituted. Air blowing improves the passivating effect. 

Next, the boiler must be passivated. The boiler is filled above normal working level and ammonia/hydrazine or a similar passivation treatment is added. The boiler is first given a hydrostatic test. Following this, the water level is dropped, and the boiler is lightly fired for 4 to 6 hours to ensure adequate passivation of the boiler surfaces. 

Equilibria considerations on solution-grown zinc chalcogenide compounds have been put forward by Chaparro [28] who examined the chemical and electrochemical reactivity of solutions appropriate for deposition of ZnS, ZnSe, ZnTe (and the oxide ZnO) in order to explain the results of recipes normally used for the growth of such thin films. The author compared different reaction possibilities and analyzed the composition of solutions containing zinc cations, ammonia, hydrazine, chalcogen anions, and dissolved oxygen, at 25 °C, by means of thermodynamic diagrams, applicable for concentrations usually employed in most studies. 

The situation does not improve with mixtures with the hydrides of the elements. Thus, a detonation occurred during contact between water and chlorine due to an accidental spark. Phosphine, silane and diborane all combust spontaneously in chlorine (their behaviour is the same in oxygen). With hydrogenated nitrogenous compounds ammonia, hydrazine, hydroxylamine, ammonium salts (especially ammonium chloride), and also sulphamic acid (these last two in an acid medium) there is ignition or even detonation. 

Metal compounds containing both coordinated ammonia, hydrazine, hydroxylamine or similar nitrogenous donors, and coordinated or ionic perchlorate, chlorate, nitrate, nitrite, nitro, permanganate or other oxidising groups will decompose violently under various conditions of impact, friction or heat [1,2]. From tabulated data for 17 such compounds of Co and Cr, it is considered that oxygenated A-coordinated compounds, (particularly those which are oxygen balanced) cover... 

Boric acid forms complexes with a number of inorganic ions and organic molecules. Ammonia, hydrazine, hydroxides and oxyhalides from complexes with boric acid. The organics include diols, thiols, dioxane, pyridine and many other solvents in which boric acid dissolves. 

Sodium bromide can be made by passing bromine through an aqueous solution of sodium hydroxide or carbonate in the presence of a reducing agent, such as ammonia, hydrazine, activated charcoal, or Fe2+ ion. A typical method involves adding iron to bromine water to form ferrosoferric bromide, FelFeBrs]. This double salt is dissolved in excess water followed by addition of sodium carbonate. The product mixture is filtered and the filtrate is evaporated to crystallize sodium bromide. The overall reaction may be written as follows ... 

Some specific properties of ZnS films grown from thiourea/ammonia/hydrazine baths, sometimes with added compounds, are given next. 

Volatile Treatment. This method of treatment may be used for units operating above 2000 psi (136 atm) drum pressure. In this method, no Solid chemicals are added lo either the boiler 01 pie-boiler cycle. By eliminating solid treatment, the volatile carry-over of solids is eliminated and consequently turbine deposits are avoided. Cycle pH is controlled at 9.0 to 9.5 with a volatile amine such as ammonia. Hydrazine is added as an oxygen scavenger in quantity sufficient to provide a concentration of 20 to 30 ppb at the economizer inlet. 

The important compounds of nitrogen with hydrogen are ammonia, hydrazine, and hy dr azoic acid, the parent of the shock-sensitive azides. Phosphine forms neutral solutions in water reaction of nonmetal halides with water—hydrolysis—produces oxoacids but no change in oxidation number. 

Even though ammonia, hydrazine, and hydrazoic acid have nitrogen-hydrogen bonds, their photochemistry is very different. In hydrazoic acid the photochemistry is dominated by the weak HN-N bond while in ammonia and hydrazine the fragmentation of the N-H bond appears to be the most important process. 

Similarly, very weak acids (such as HCN) may be titrated easily in ammonia, hydrazine, or in organic amines, the end points being far sharper... 

Since chloramine itself is prepared by chlorination of ammonia, hydrazine is generally prepared by treatment of excess ammonia with chlorine. The similarity to H2O2 is exemplified by the detection of hydrazine at the anode in electrolysis of ammonium salts, just as H2Q2 or its derivatives can result from electrolysis of aqueous acid solutions. 

The similarities between ammonia, hydrazine, and hydroxylamine extend into organic chemistry. The three bases form analogous classes of... 

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