Ammonium hydroxyl

Alkaline solutions of mononitroparaffins undergo many different reactions when stored for long periods, acidified, or heated. Acidification of solutions of mononitro salts is best effected slowly at 0°C or lower with weak acids or buffered acidic mixtures, such as acetic acid—urea, carbon dioxide, or hydroxyl ammonium chloride. If mineral acids are used under mild conditions, eg, dilute HCl at 0°C, decomposition yields a carbonyl compound and nitrous oxide (Nef reaction). 

Shriadah and Ohzeki [350] determined iron in seawater by densitometry after enrichment as a bathophenanthroline disulfonate complex on a thin layer of anion exchange resin. Seawater samples (50 ml) containing iron (II) and iron (III) were diluted to 150 ml with water, followed by sequential addition of 20% hydrochloric acid (100 xl), 10% hydroxyl-ammonium chloride (2 ml), 5 M ammonium solution (to pH 3.0 for iron (III) reduction), bathophenanthroline disulfonate solution (1.0 ml), and 10% sodium acetate solution (2.0 ml) to give a mixture with a final pH of 4.5. A macroreticular anion exchange resin in the... 

Determine (a) the pH of a 0.0240 m hydroxyl-ammonium chloride (more commonly called hydroxylamine hydrochloride) solution (b) the pH of 0.010 M Na2C03(aq). 

Ammonium ions produce hydrogen atoms on interaction with e aq but the H/D isotope effect involved in producing these H atoms (H/D = 4.36 after correction for the residual H, H/D = 4.33 for photolyti-cally produced eaq (16)) indicates the formation of NH4 as intermediate which then dissociates to NH8 + H. These assumptions are in accord with the observed behavior of alkyl ammonium ions which, on interaction with e aq produce alkyl radicals rather than H atoms (52) RNH8 + + e aQ - RNH8 - NH8 + R. Hydroxyl ammonium ions behave similarly yielding NH2 radicals rather than H atoms (52, 89) NH8OH + + — NH8OH — NH2 + H20. 

Solution B (0.5molT1 hydroxylammonium chloride). Dissolve 34.75 g of hydroxyl-ammonium chloride in 400 ml of distilled water. Transfer the solution into a 11 calibrated flask and add, by means of a calibrated pipette, 25 ml of 2 mol l-1 HN03 (prepared by weighing from a suitable concentrated solution). Make up to volume with distilled water. Prepare this solution on the same day the extraction is carried out. 

Reagents. Potassium bromate (0.1 N)—potassium bromide (1% m/v) solution dissolve 2.784 g anhydrous potassium bromate in distilled water add 10 g potassium bromide and dilute to one litre with distilled water. Hydrochloric acid (sp. gr. 1.18). Sodium chloride (12% m/v)—hydroxyl-ammonium chloride (12% m/v) solution. 

NaN03 +NaHS03+H2S04+ N(S03 Na)2 OH+H2 O. Heating of the resulting soln produces hydroxyl-ammonium hydrogen sulfate ... 

In crystalline NH2OH the N-0 bond length is found to be 1-47 (0-03) A. The H atoms were not located, but their probable positions were deduced from a reasonable hydrogen bonding scheme. We have referred earlier to hydroxyl-ammonium salts. 

The gas is bubbled through a bubbler containing hydroxyl ammonium chloride and analyzed by colorimetry. 

Hydroxyl ammonium chloride 1% (w/v) hydroxyl ammonium chloride, freshly made in PBS. 

Incubate slides in hydroxyl ammonium hydrochlonde solution for 15 min and bnefly wash in PBS for 5 min prior to hybridization. 

The SeBrz is decomposed in aqueous solution (in the distillation receiver) according to SeBrz + 3 H2O—H2Se03 + 4 HBr to give selenious acid which reacts with o-phenylenediamine. Excess bromine is bonded with hydroxyl-ammonium chloride. Any Se(VI) which is present is reduced to Se(IV) by HBr. The detection therefore always encompasses total selenium. 

Di Gianni et al2 have reported the modification of commercial clay containing a hydroxylated ammonium ion (commercially known as Cloisite 15)... 

The causes of allergic contact dermatitis (31 cases) were rubber chemicals (6 cases), nickel (5 cases), phenol formaldehyde resin (3 cases), epoxy resin (3 cases), formaldehyde (2 cases), medications (2 cases), and chromium, dibutylhiourea (Kanerva et al. 1998), 4,4 -diphenylmethane diisocyanate (MDI), glutaralde-hyde, hydroxyl ammonium chloride (Estlander et al. i997 )> methacrylates, 2V-methyl-N-nitroso-p-toluene-sulfonamide (Estlander et al. 1996a) and potassium persulfate (1 case each), and unspecified agents (2 cases). 

Estlander T, Jolanki T, Kanerva L (1997) Hydroxyl-ammonium chloride as sensitizer in a water laboratory. Contact Dermatitis 36 161-162 Goh CL (1990) Allergic contact dermatitis and onycholysis from hydroxylamine sulphate in colour developer. Contact Dermatitis 22 109 Scheman AJ, Katta R (1997) Photographic allergens an update. Contact Dermatitis 37 130... 

---