POTASSIUM PEROXIDE K2O2

Properties potassium peroxide K2O2:

White (with a impurity of KO2 - light yellow). When heated in air turns yellow and decomposes, melts at a pressure of O2. It has an ionic structure (K+)2(O22-). Sensitive to CO2 of air. Completely decomposed by water, acids, react with metals and nonmetals. Exhibits redox properties.


Obtaining potassium peroxide K2O2:

K + O2 (air) = KO2 (combustion, impurity K2O2), + K → K2O2↓ → (O2, time) → KO2↓ (- 50° C, in the liquid NH3).

KO2 → (-O2, 290° C, vacuum) K2O2 → (-O2, 530° C) → K2O.

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

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


Chemical reactions with potassium peroxide K2O2:

2 K2O2 = 2 K2O + O2 (t > 500° C).

K2O2 + 2 H2O (cold) = 2 KOH + H2O2,

2 K2O2 + 2 H2O (hot) = 4 KOH + O2.

K2O2 + 2 HCl (diluted, cold) = 2 KCl + H2O2.

2 K2O2 + 2 H2SO4 (diluted, hot) = 2 K2SO4 + 2 H2O + O2↑.

K2O2 + O2 (air) = 2 KO2 (normal temp.).

2 K2O2 + 2 CO2 = 2 K2CO3 + O2,

K2O2 + CO = K2CO3 (normal temp.).

2 K2O2 + C (graphite) = K2CO3 + K2O (100° C).

5 K2O2 + 8 H2SO4 (diluted) + 2KMnO4= 5 O2↑ + 2 MnSO4 + 6 K2SO4 + 8 H2O.

 

Did you know?

Although oxygen gas is colorless (light refraction aside), both the liquid and solid forms are blue.