Potassium chlorate thermal decomposition

Decomposition reactions are reactions in which a compound breaks down into two or more simpler substances. Although not all decomposition reactions are redox reactions, many are. For example, the thermal decomposition reactions, such as the common laboratory experiment of generating oxygen by heating potassium chlorate, are decomposition reactions ... 

Unexpectedly we find that the bromate(V) ion in acid solution (i.e. effectively bromic(V) acid) is a more powerful oxidising agent than the chlorate(V) ion, CIO3. The halates(V) are thermally unstable and can evolve oxygen as one of the decomposition products. Potassium chlorate(V), when heated, first melts, then resolidifies due to the formation of potassium chlorate(VII) (perchlorate) ... 

Chemical Properties. On thermal decomposition, both sodium and potassium chlorate salts produce the corresponding perchlorate, salt, and oxygen (32). Mixtures of potassium chlorate and metal oxide catalysts, especially manganese dioxide [1313-13-9] Mn02, are employed as a laboratory... 

Oxygen occurs free in air in which it forms 21% by volume. It is also found combined with hydrogen in water and constitutes 86% of the oceans, and with other elements such as minerals constituting ca 50% of the earth s crust. In the laboratory it is usually prepared by the thermal decomposition of potassium chlorate in the presence of manganese dioxide catalyst ... 

Write the balanced chemical equation for (a) the thermal decomposition of potassium chlorate without a catalyst (b) the reaction of bromine with water (c) the reaction between sodium chloride and concentrated sulfuric acid, (d) Identify each reaction as a Bronsted acid—base, Lewis acid—base, or redox reaction. 

Action of chlorine trifluoride causes incandescence [1]. Manganese dioxide catalytically decomposes powerful oxidising agents, often violently. Dropped into cone, hydrogen peroxide, the powdered oxide may cause explosion [2], Either the massive or the powdered oxide explosively decomposes 92% peroxomonosulfuric acid [3], and mixtures with chlorates ( oxygen mixture , heated to generate the gas) may react with explosive violence [4], Cuban pyrolusite can be used in place of potassium dichromate to promote thermal decomposition of potassium chlorate in match-head formulations [5],... 

Pyrotechnic mixtures "burn," but it must be remembered that these materials supply their OWTl oj gen for combustion, through the thermal decomposition of an oxygen-rich material such as potassium chlorate... 

FIG. 5.5 Thermogram of pure potassium chlorate, KCIO thermal events are observed prior to the melting point (356°Q. Exothermic decomposition occurs above the melting point as oxygen gas is liberated. 

Another important factor is the thermal stability and heat of decomposition of the oxidizer. Potassium chlorate mixtures tend to be much more sensitive to ignition than potassium nitrate compositions, due to the exothermic nature of the decomposition of KCIO 3. Mixtures containing very stable oxidizers - such as ferric oxide (Fe 2O 3) and lead chromate (PbCrO 4) - can be quite difficult to ignite, and a more-sensitive composition frequently has to be used in conjunction with these materials to effect ignition. 

K. Yamamoto, Primary Explosives. III. Thermal Decomposition and Initiation of Primary Explosive-Potassium Chlorate Initiating Compositions , KKK 25 (3), 126-34 (1964). CA 61, 11839(1964)... 

Reaction rates are affected not only by reactant concentrations and temperature but also by the presence of catalysts. A catalyst is a substance that increases the rate of a reaction without being consumed in the reaction. An example is manganese dioxide, a black powder that speeds up the thermal decomposition of potassium chlorate ... 

Small amounts of 02 can be prepared in the laboratory by electrolysis of water, by decomposition of aqueous hydrogen peroxide in the presence of a catalyst such as Fe3+, or by thermal decomposition of an oxoacid salt, such as potassium chlorate, KC103 ... 

Qualitative and quantitative analysis show that a catalyst undergoes no change in mass or chemical composition. However, it may undergo a physical change. Thus, granular manganese dioxide (Mn02) used as a catalyst in the thermal decomposition of potassium chlorate is left as a fine powder at the end of the reaction. 

Thermal decomposition of potassium chlorate (KCIO3) in the presence of manganese dioxide (Mn02). 

Johnson and MTntosh 4 found from 6-2 to 8-9 per cent, of carbon monoxide in the gases evolved during the combustion of a mixture of carbon with excess of potassium chlorate, both in air and m a vacuum. As the temperature was only of the order of 1000° C., the authors argue that the monoxide could not have resulted from the thermal decomposition of the dioxide, so that the monoxide would appear to be the first product in the combustion of solid carbon. 

When the reactants and the catalyst are in the same physical state the catalyst is called a homogeneous catalyst e.g. concentrated sulfuric acid speeds up the reaction between ethanoic acid and ethanol to form the ester, ethyl ethanoate. Manganese(IV) oxide catalyses the thermal decomposition of potassium chlorate(V) to give oxygen. 

The value of i p is 27 for the thermal decomposition of potassium chlorate at a given high temperature. What is the partial pressure of oxygen in a closed container in which the following system is at equilibrium at the given temperature (This can be a dangerous reaction.)... 

Bowden and Singh [37, 38] achieved explosion of lead and silver azides when crystals were irradiated with an electron beam of 75 kV and 200 pA. Explosion was partly due to heating of the crystals by the electron beam. To substantiate this, crystals of potassium chlorate with a melting point of 334°C readily melted in the beam, showing a temperature rise close to the explosion temperature of the azides. Sawkill [97] investigated with an electron microscope the effect of an electron beam on lead and silver azides. If explosion did not take place, color changes and nucleation occurred cracks developed within the crystals which broke up into blocks about 10 cm across and were believed to be associated with a substructure in the crystals. In silver azide the progression to silver was pronounced but did not follow the thermal decomposition route. 

A common laboratory preparation of oxygen gas is the thermal decomposition of potassium chlorate (KCIO3). Assuming complete decomposition, calculate the number of grams of O2 gas that can be obtained from 46.0 g of KCIO3. (The products are KCl and O2.)... 

CALCIUM PHOSPHINATE (7789-79-9) Ca(HjPOi)2 Noncombustible solid. Incompatible with strong acids strong reducing agents (may release toxic and flammable phosphine gas) strong oxidizers (partial decomposition may release oxides of phosphorus). Shock- and heat-sensitive mixture formed with potassium chlorate may cause violent reaction or ignition. Thermal decomposition forms flammable phosphine. Mixtures with perchloric acid may form explosive materials when heated. CALCIUM PYROPHOSPHATE (7758-87-4 10103-46-5) Ca3(P04)j... 

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