Potassium Nitrate KNOj

Oxygen can be produced by electrolysis of water using a salt as an electrolyte that produces hydrogen at the opposite electrode. When potassium chlorate (KClOj) is heated in a test tube with a small amount of manganese dioxide (MnO ) as a catalyst, the chemical reaction that releases the oxygen from potassium chlorate will be accelerated. Use of potassium nitrate (KNOj) will also produce small amounts of oxygen. 

Chilean saltpeter [potassium nitrate (KNOj)] has a number of impurities, including sodium and calcium iodate. Iodine is separated from the impurities and, after being treated chemically, finally produces diatomic iodine. Today, iodine is mostly recovered from sodium iodate (NalO ) and sodium periodate (NalO ) obtained from Chile and Bohvia. 

POTASSIUM NITRATE KNOj saltpeter, niter Drug store... 

Carbon dioxide (CO2) 11.2 Nitrogen (N2) 4.2 Carbon monoxide (CO) 1.1 Water vapor (HjO) 1.1 Hydrogen sulfide (H2S) 0.1 Methane (CH4 0.1 Hydrogen (Hj) 34.1 Potassium carbonate (KjCOj) 8.4 Potassium suifate (K2SO4) 8.1 Potassium suifide (KjS) 4.9 Suifur(S) 0.2 Potassium nitrate (KNOj) 0.1 Potassium thiocyanate (KSCN) 0.1 Ammonium carbonate ((NH4)2CO ) 0.1 Carbon (C)... 

The main difference between air and liquid is that other forces start to intrude, especially double-layer forces at long range and solvation forces at ranges less than a nanometer. The double-layer forces can be seen quite easily in the surface force apparatus. At pH around 6 in potassium nitrate (KNOj) solutions of various concentrations, the force was a repulsion which increased exponentially as the gap closed. For higher concentrations of salt, the slope increased as expected from DLVO theory (see Chapter 10). Results are shown in Fig. 6.12 for several concentrations ofKNOj, ranging from 10 M to 10 M. 

Elemental potassium is so soft that it can be cut with a knife. It oxidizes immediately on exposure to air and reacts violently with water. As hydrogen gas is evolved in this reaction and bums spontaneously, potassium is always stored under a liquid such as kerosene. Potassium and its salts impart a Hlac color to flames. Potassium carbonate, also called potash or pearl ash, is an important raw material for making glass and soft soap. Caustic potash is potassium hydroxide KOH. Potassium nitrate KNOj occurs naturally as saltpeter and is used in matches, explosives and fireworks and in pickling meat Potassium chloride KCl is an important potassium fertilizer. In living beings potassium ions are important for the transmission of nerve impulses. 

Alumina loaded with potassium as solid base catalyst was prepared and tested for the transesterification of soybean oil. Potassium nitrate (KNOj-SS wt%) on AljOj followed by calcinations at 773K for 5 h was found to be the active catalyst for transesterification at reflux temperature of methanol with oil to methanol ratio of 1 15, catalyst amount of 6.5% with 7 h of reaction time, which gave a conversion of 87% [42]. It was postulated that KNOj transformed to KjO or Al-O-K composites, which were proposed to be present in the active sites of the catalyst. In a similar type of study, KNO3 (35 wt%) loaded on Al Oj was used as catalyst for transesterification of jatiopha oil gave 84% conversion with oil to methanol ratio of 1 12 at 70° C and the authors showed that the catalyst can be used for three times [43]. 

Potassium nitrate nonahydrate, KNOj.OH O oxidizing, irritating... 

When a compound that can form several modiflcations crystallizes, flrst a modiflcation may form that is thermodynamically unstable under the given conditions afterwards it converts to the more stable form (Ostwald step rule). Selenium is an example when elemental selenium forms by a chemical reaction in solution, it precipitates in a red modiflcation that consists of Se molecules this then converts slowly into the stable, gray form that consists of polymeric chain molecules. Potassium nitrate is another example at room temperature jS-KNOj is stable, but above 128 °C a-KNO3 is stable. From an aqueous solution at room temperature a-KNO3 crystallizes flrst, then, after a short while or when triggered by the slightest mechanical stress, it transforms to )3-KNO3. 

Potassium nitrate (saltpeter) has a molecular formula of KNOj. It is found as a transparent to white crystalline powder and as crystals. Potassium nitrate is water-soluble and is a dangerous fire and explosion risk when heated or shocked or in contact with organic materials. It is a strong oxidizing agent, with a four-digit UN identification number of 1486. Potassium nitrate is used in the manufacture of pyrotechnics, explosives, and matches. It is often used in the illegal manufacture of homemade pyrotechnics and explosives. 

Sodium is very reactive and cannot be allowed to remain in the bag after detonation. Potassium nitrate is added to the solid mixture to react with the sodium 10 Na + 2 KNOj KjO + 5 Na20 + Nj. Notice that this reaction produces even... 

The use of nitrates and nitrites in cured meat products must comply with the provisions set out in Directive 2006/52/EC, which amends Directive 95/2/EC on additives other than colours and sweeteners. Currently authorised as food additives are sodium and potassium nitrites and sodium and potassium nitrates that may be sold only in a mixture with salt or a salt substitute. The indicative ingoing amount of potassium and sodium nitrites that are authorised for use are 150mg/kg and the residual amount is 50mg/kg (KNOj) in non-heat-treated, dried meat products, 100 mg/kg (NaNOj) in other cured meat products, canned meat products and 175 mg/kg (NaNOj) in cured bacon. The indicative ingoing amount of potassium and sodium nitrates is 300 mg/kg in all cured products and the residual amount in cured and canned meat products is 250 mg/kg, in pickled herring and sprat 200 mg/kg and in hard, semi-hard and semi-soft cheeses and dairy-based cheese analogues 50 mg/kg. 

Fig. 5.29 The mean apparent molar volumes in the tripotassium citrate + potassium nitrate + water systems at 25°C as a function of the total molal concentration in solutions. - K3Cit, - KNOj,...

Silver nitrite. Warm concentrated solutions of silver nitrate (containing 48 g. of AgNOj) and potassium nitrite (containing 30 g. of KNOj) are mixed, and the mixture is allowed to cool. The silver nitrite which separates is filtered off and washed with water. It may be recrystallised from water at 70°, and is dried either in a vacuum desiccator or in an air oven at about 40° the yield is about 90 per cent. Silver nitrite should be stored in an tightly-stoppered amber bottle. 

A 50cm3 aliquot of a lead nitrate solution in 0.1 M KNOj was titrated ampero-metrically with 0.05 M potassium dichromate. The burette readings and corresponding values of cell curreni were as follows ... 

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