POTASSIUM HYDROXIDE KOH

Properties potassium hydroxide KOH:

Caustic potash. White, very hygroscopic, melts and boils without decomposition. Readily soluble in water with a strong exothermic effect, creates a high alkaline environment. Exhibits properties of basic hydroxides (refers to alkali), neutralized by acids, reacts with oxides of nonmetals, amphoteric oxides and hydroxides. Vigorously absorbs moisture from the air and CO2. Reacts with non-metals, metals.


Molar mass g/mol 56.11
Density g/cm3 2.044
Melting point °C 404
Boiling point °C 1324

Obtaining potassium hydroxide KOH:

2 K + 2 H2O = 2 KOH + H2↑.

4 K + O2 + 2 H2O = 4 KOH.

K2CO3 + Ca(OH)2 (saturated) = CaCO3↓ + 2 KOH.

2 KCl + 2 H2O → Electrolysis H2↑ (cathode) + Cl2(anode) + 2KOH,

2 KCl(melt) (on Hg-cathode)→Electrolysis→ 2K(cathode) + Cl2(anode).


Chemical reactions with potassium hydroxide KOH:

KOH·2H2O = KOH-H2O + H2O (33-40° C, vacuum),

KOH·H2O = KOH + H2O (500° C, vacuum).

KOH (diluted) + 6 H2O = [K(H2O)6](+) + OH(-).

KOH + HCl (diluted) = KCl + H2O,

KOH + HNO3 (diluted) = KNO3 + H2O.

2 KOH + H2SO4 (diluted) = K2SO4 + 2H2O,

KOH + H2SO4 (conc., cold) = KHSO4 + H2O.

KOH (diluted) + H3PO4 (conc.) = KH2PO4 + H2O,

2 KOH (diluted) + H3PO4 (diluted) = K2HPO4 + 2H2O.

3 KOH (conc.) + H3PO4 (diluted) = K3PO4 + 3H2O.

KOH (diluted) + HF (diluted) = KF + H2O,

KOH (conc.) + 2 HF (conc.) = KHF2 + H2O.

KOH (conc.) + HCN = KCN + H2O.

2 KOH (conc., cold) + E2 = KEO + KE + H2O (E = Cl, Br, I),

6 KOH (conc., hot) + 3E2 = KEO3 + 5KE + 3H2O.

12 KOH (conc., hot) + 5 Cl2 + Br2 = 2 KBrO3 + 10 KCl + 6 H2O.

4 KOH + 4O3 = 4 KO3 + O2 + 2 H2O (to 20° C).

2 KOH + 2K = 2 K2O + H2 (400-450° C).

2 (KOH-2H2O) + 2 Al = 2 KAlO2 + 3 H2 + 2 H2O

2 KOH (conc.) + 6 H2O (hot) + 2 Al = 2 K[Al(OH)4] + 3 H2 ↑.

2 KOH (conc.) + EO2 = K2EO3 + H2O (E = C, S),

KOH + EO2 = KHEO3↓ (in ethanol).

6 KOH (conc.) + 5 SiO2 = K4SiO4 (solution) + K2Si4O9 ↓ + 3 H2O.

4 KOH + 6 NO = 4 KNO2 + N2 + 2 H2O (400° C).

2 KOH (diluted) + 2 NO2 = KNO2 + KNO3 + H2O.

2 KOH (cold) + NO + NO2 = 2 KNO2 + H2O,

4 KOH (hot) + 4 NO2 + O2 = 4 KNO3 + 2 H2O.

2 KOH + Al2O3 = 2 KAlO2 + H2O (900-1100° C).

KOH + Al(OH)3 = KAlO2 + 2 H2O (1000° C).

2 KOH (conc., hot) + 3 H2O + Al2O3 = 2K[Al(OH)4].

KOH (conc.) + Al(OH)3 = K[Al(OH)4].

KOH (conc.) + NH4Cl (conc.) = KCl + NH3 ↑ + H2O (boiling).

2 KOH + FeI2 = 2 KI + Fe(OH)2↓ (in atmosphere N2),

2 KOH (diluted) + 2 AgNO3 = Ag2O↓ + H2O + 2 KNO3.

3 KOH (diluted) + AlCl3 = Al(OH)3↓ + 3 KCl.

4 KOH (conc.) + AlCl3 = K[Al(OH)4] + 3 KCl.

KOH (conc.) + 2 H2S + 4 SO2 = 3 K2SO3S + 5H2O.

KOH + (2-4) H2O2 (conc.) →time→ K2O2·(2-4)H2O2↓ (0° C),

K2O2·(2-4) H2O2 →time→ K2O2 + (2-4) H2O2 (over conc. H2SO4).

4KOH (melt)→Electrolysis→ 4K (cathode) + O2↑(anode) + 2H2O.


 

Did you know?

The only letter that doesn't appear on theperiodic table is J.