^^K2CO3 potassio carbonato. Potassa. Cenere.

Dal carpino nero della Lunigiana alla potassa caustica.

Esp: Preparazione lisciva: bollire le ceneri di legno.

Per secoli la lisciva Ŕ stata il migliore detergente da bucato.

Esp: Preparazione del carbonato di potassio dalla cenere di legno

http://www.itchiavari.org/chimica/lab/k2co3.html

Potash, potassa.

potash =  obtained leaching the ash of burnt wood or tree leaves and evaporating the solution in a pot.

K2CO3 Potassium carbonate is the primary component of potash, because plants have little or no sodium content, and the rest of a plants' major mineral content consists of calcium salts of low water solubility.

K2CO3 Potassium carbonate

Pearl ash or salts of tartar

Historically created by baking potash in a kiln to remove impurities.

Composizione delle ceneri di combustione. Come si forma K2CO3  nelle ceneri della combustione?

K2O ossido di potassio, Potassium_oxide

K2O A contatto con l'acqua, reagisce violentemente formando KOH idrossido di potassio. Il composto Ŕ corrosivo e fortemente irritante.

KOH, idrossido di potassio, Potassium_hydroxide, Calcinated or caustic potash.

Processo di caustificazione del K2CO3 con Ca(OH)2:

KOH historically was made by boiling a solution of potash with slaked lime

 

 

K2CO3 + Ca(OH)2 → CaCO3 + 2 KOH

K2CO3 Potassium carbonate
Ca(OH)2 Calcium hydroxide
CaCO3 Calcium carbonate
KOH Potassium hydroxide

a metathesis reaction which caused CaCO3  to precipitate, leaving  KOH  in solution. Filtering off the precipitated  CaCO3  and boiling down the solution gives KOH.

  Massa molare

[g/mol]

SolubilitÓ in acqua
Ca(OH)2 74,1 1,7 g/l a 293 K
K2CO3 138,2 1120

1560

g/L (20 ░C)
g/L (100 ░C)
CaCO3 100,1 0,00015  mol/L (25░C)
KOH 56,1 1130 g/L (20 ░C)

Potassium

Potassium metal was first isolated in 1807 in England by Sir Humphry Davy, who derived it from caustic potash (KOH), by the use of electrolysis of the molten salt with the newly discovered voltaic pile. Potassium was the first metal that was isolated by electrolysis. Later in the same year, Davy reported extraction of the metal sodium from a mineral derivative (caustic soda, NaOH, or lye), not a plant salt, by a similar technique, demonstrating the elements, and thus the salts, to be different.

A reaction of potassium metal with water. >>>

Hydrogen is liberated that burns with a pink/lilac flame, the flame color owing to burning potassium vapour. Strongly alkaline potassium hydroxide is formed in solution.

Ca(OH)2 idrossido di calcio, Calcium_hydroxide, calce spenta o calce idratata. Slaked lime.

Se riscaldato a 512 ░C l'idrossido di calcio si decompone in ossido di calcio e acqua.

CaO ossido di calcio, calce, calce viva

CaCO3 calcium carbonate

Wikipedia

K2CO3 Potassium carbonate, Carbonato di potassio

Carbonate

 

 

      H2CO3  
      CO32- HCO3-
    idrrossido carbonato bicarbonato
Na   NaOH Na2CO3 NaHCO3
K K2O

 

KOH K2CO3 KHCO3
Ca CaO Ca(OH)2 CaCO3 Ca(HCO3)2

 

 

CO32− +2 H2O ↔ HCO3 + H2O + OH ↔ H2CO3 +2 OH

H2CO3 +2 H2O ↔ HCO3 + H3O+ + H2O ↔ CO32− +2 H3O+