Ammonium peroxodisulphate

Ammonium peroxodisulphate detonates when it is heated above 75°C, but there is the same result at ambient temperature in the presence of water, carbon dioxide or sodium peroxide. 

Detonation occurs during the reaction of molten aluminium with ammonium peroxodisulphate in the presence of water. However, since the temperature is above 75°C, the presence of water is sufficient to decompose it and the water/molten aluminium interaction has aiready been mentioned as being explosive. 

Finally, there is an extremely violent reaction during the action of ammonia on ammonium peroxodisulphate in the presence of Ag- ions. 

Pyridinediylbisphosphonium salts react with methanol in the presence of ammonium peroxodisulphate to give the 5-hydroxymethylated compound when radical conditions were absent, nucleophiles gave the 4-substituted products selectively746. 

Hydrogen peroxide (a) or ammonium peroxodisulphate (b), when added to a solution of tetrahydroxoplumbate(II) forms a black precipitate of lead dioxide by oxidizing bivalent lead to the tetravelent state ... 

To study these reactions use a freshly prepared 0 1m solution of ammonium peroxodisulphate (NH4)2S208. 

Method A This procedure involves the removal of the bromide and iodide (but not chloride) by oxidation with potassium or ammonium peroxodisulphate in the presence of dilute sulphuric acid. The free halogens are thus liberated, and may be removed either by simple evaporation (addition of water may be necessary to maintain the original volume) or by evaporation at about 80° in a stream of air. 

Sodium bismuthate This reagent, in the presence of dilute nitric acid, converts cerium(III) ions into cerium(IV) in the cold. A similar result is obtained by heating with ammonium peroxodisulphate or with lead dioxide and dilute nitric acid (1 2). In all cases, the solutions become yellow or orange in colour. 

Add solid potassium or ammonium peroxodisulphate to the solution of the mixed halides contained in a conical flask strongly acidify with dilute sulphuric acid heat the flask to about 80°, and aspirate a current of air through the solution with the aid of a filter pump (see Fig. IV.2 in Section IV.45, 5) until the solution is colourless. Add more solid peroxodisulphate or water as may be found necessary. Test the residual colourless liquid for chloride with silver nitrate solution and dilute nitric acid. 

Ammonium peroxodisulphate (m). Dissolve 22 8 g ammonium peroxodisul-phate, (NH4)2S208, in water and dilute to 100 ml. 

Ammonium peroxodisulphate, (NH4)2S20g, is produced at the anode when a mixture of (NH4)2S04 and H2SO4 is electrolysed. The less soluble potassium salt can be precipitated by adding KHSO4 to the solution ... 

Oxygen content, point of zero charge and Boehm titration of a series of activated carbons oxidized with nitric acid and ammonium peroxodisulphate [207]. Reprinted with permission from C.O. Ania, J.B. Parra, J.J. Pis, Ads. Sci. Technol., 22 (2004) 337... 

The interfering yellow coloration caused by iron (III) ions is eliminated by adding 1 ml of cone, phosphoric acid before oxidation with ammonium peroxodisulphate. 

If relatively high concentrations of organic substances are present, add 3 ml of ammonium peroxodisulphate solution following evaporation and boil the sample for 30 minutes. 

Allow the sample to cool, then add in succession 5 ml of 0.1 m silver nitrate solution and 10 ml of 1 % ammonium peroxodisulphate solution. Heat to gently boiling for 30 min. The total volume of the sample must... 

In the presence of a strong oxidizing agent such as bromine or ammonium peroxodisulphate, nickel (II) ions form a wine-red to brown-coloured... 

Next treat the hydrochloric solution containing the nickel with 3 ml of diacetyl dioxime solution, 1 ml of 10 m sodium hydroxide solution and 0.3 ml of ammonium peroxodisulphate solution, mixing well each time. Dilute with water to the mark at 20 C, leave to stand for about 2 hours, and measure in a 3-cm cuvette at 60 nm against distilled water. Carry out a blank test concurrently and take into account accordingly. 

Polymerisation of vinyl toluene in quaternary microemulsions containing cetyltrimethylammonium bromide as the cationic surfactant was studied using laser Raman spectroscopy and dilatometry. The influences of water soluble (potassium peroxodisulphate, ammonium peroxodisulphate) and oil-soluble (azobisisobutyronitrile, benzoyl peroxide) initiators, monomer, surfactant, cosurfactants (n-alcohol and bifunctional alcohols) and temperature on the rates of polymerisation, energy of activation, particle diameter, number of polymer particles, molecular weight of polyvinyl toluene and number of polymer chains per latex particle were investigated. The dependencies of the kinetic and latex size parameters on the initiators and co-surfactants are discussed in terms of the efficiency of the initiators in initiating the polymerisation and on the interfacial partitioning behaviour of various co-surfactants. 19 refs. 

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