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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 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.
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.
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 ...
A 3–5% aqueous solution of KOH is applied to the flesh of a mushroom and the researcher notes whether or not the color of the flesh changes. Certain species of gilled mushrooms , boletes , polypores , and lichens [ 25 ] are identifiable based on this color-change reaction.
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).
The alkaline battery gets its name because it has an alkaline electrolyte of potassium hydroxide (KOH) instead of the acidic ammonium chloride (NH 4 Cl) or zinc chloride (ZnCl 2) electrolyte of the zinc–carbon batteries. Other battery systems also use alkaline electrolytes, but they use different active materials for the electrodes.
Potassium hexacyanidoferrate(II) is used in a mixture with potassium ferricyanide and phosphate buffered solution to provide a buffer for beta-galactosidase, which is used to cleave X-Gal, giving a bright blue visualization where an antibody (or other molecule), conjugated to Beta-gal, has bonded to its target. On reacting with Fe(3) it gives a ...