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The modern commercial production of potassium carbonate is by reaction of potassium hydroxide with carbon dioxide: [3] 2 KOH + CO 2 → K 2 CO 3 + H 2 O. From the solution crystallizes the sesquihydrate K 2 CO 3 ·1.5H 2 O ("potash hydrate"). Heating this solid above 200 °C (392 °F) gives the anhydrous salt.
Aqueous alkaline solutions do not reject carbon dioxide (CO 2) so the fuel cell can become "poisoned" through the conversion of KOH to potassium carbonate (K 2 CO 3). [2] Because of this, alkaline fuel cells typically operate on pure oxygen, or at least purified air and would incorporate a 'scrubber' into the design to clean out as much of the ...
It is manufactured by treating an aqueous solution of potassium carbonate or potassium hydroxide with carbon dioxide: [1] K 2 CO 3 + CO 2 + H 2 O → 2 KHCO 3. Decomposition of the bicarbonate occurs between 100 and 120 °C (212 and 248 °F): 2 KHCO 3 → K 2 CO 3 + CO 2 + H 2 O. This reaction is employed to prepare high purity potassium carbonate.
The temperature of the solution eventually decreases to match that of the surroundings. The equilibrium, between the gas as a separate phase and the gas in solution, will by Le Châtelier's principle shift to favour the gas going into solution as the temperature is decreased (decreasing the temperature increases the solubility of a gas).
[4]: 98 At the end of the reaction the quantity of KOH is determined by titration using standard solution of hydrochloric acid (HCl). Key to the method is the use of phenolphthalein indicator, which indicates the consumption of strong base (KOH) by the acid, not the weak base (potassium carboxylates).
Potassium hypochlorite is produced by the disproportionation reaction of chlorine with a solution of potassium hydroxide: [2] Cl 2 + 2 KOH → KCl + KOCl + H 2 O. This is the traditional method, first used by Claude Louis Berthollet in 1789. [3] Another production method is electrolysis of potassium chloride solution.
The solution so produced is sufficiently reactive that it spontaneously ignites if combustible material (sugar, paper, etc.) is present. Candy being dropped into molten salt In schools, molten potassium chlorate is used in screaming jelly babies , Gummy bear , Haribo , and Trolli candy demonstration where the candy is dropped into the molten salt.
Free-radical reactions depend on one or more relatively weak bonds in a reagent. Under reaction conditions (typically heat or light), some weak bonds homolyse into radicals, which then induce further decomposition in their compatriots before recombination. Different mechanisms typically apply to reagents without such a weak bond.