Potassium Oxide Formula – Structure, Properties, Uses, Sample Questions

Potassium oxide is an ionic mixture of potassium and oxygen. It serves as a basis. This pale yellow solid is the most basic form of potassium oxide. It’s a highly reactive compound that you’ll only come into on rare occasions. Some industrial commodities, such as fertilisers and cement, are tested using the percent content of K₂O as a reference. When potassium is oxidised, the oxide, K₂O, is formed as a grey crystalline substance; potassium is burned in excess oxygen to generate potassium oxide. When dissolved in water, potassium oxide is a very corrosive alkali.

What is Potassium Oxide?

K₂O is the chemical formula for potassium oxide, an inorganic molecule. When metallic potassium combines with oxygen, it produces this substance. Potassium oxide is an alkaline substance. It interacts strongly with moisture to generate potassium hydroxide due to its deliquescent nature. It decomposes at temperatures exceeding 300 degrees Celsius.

Structure of Potassium Oxide 

Two atoms of potassium and one atom of oxygen make up the potassium Oxide formula. Bonds link these atoms together. The oxidation state of potassium is +1. The oxidation state of oxygen is -2. Two atoms of potassium unite with one atom of oxygen to balance the valency.

 

Preparation of Potassium Oxide 

• The interaction between oxygen and potassium produces potassium oxide, which is then converted to potassium peroxide, K₂O₂. The oxide is produced by treating peroxide with potassium:

K₂O₂ + 2K   ⇢   2K₂O

• K₂O can also be made by heating potassium nitrate with metallic potassium, which is a more convenient method:

2KNO₃ + 10K   ⇢   6K₂O + N₂

• Another option is to heat potassium peroxide to 500°C when it decomposes into pure potassium oxide and oxygen.

2K₂O₂  ⇢  2K₂O + O₂

• Although potassium hydroxide cannot be dehydrated further to make potassium oxide, it can react with molten potassium to do so, releasing hydrogen as a byproduct.

2KOH + 2K  ⇌  2K₂O + H₂

Physical Properties of Potassium Oxide

1. It has a pale yellow tint and is solid.
2. 94.2 g/mol is the molecular weight.
3. It has a density of 2.35 gm/cm³.
4. Potassium oxide has a melting point of 740°C.
5. It can be dissolved in ether and ethanol.

Chemical Properties of Potassium Oxide

• Potassium oxide is formed when potassium is burned in the atmosphere (O2).

​4K + O2 → 2K₂O

• When potassium hydroxide is combined with water, the result is potassium hydroxide.

K₂O + H₂O → KOH

• When it comes into contact with a strong acid, it produces salt and water.

K₂O + HCl → KCl + H₂O

• Potassium can be added to water immediately.

2K + 2H₂O → 2KOH + H₂

Uses of Potassium Oxide

1. It is used as a fertiliser in agriculture, but it may also be used to make glass and soap, and in tiny amounts, it can be utilised for medical purposes.
2. It is highly stable and insoluble in water. It’s very important in the ceramics industry because of this. It’s utilised in aircraft to make lightweight bowls and structural compositions.
3. It’s been used to treat actinomycosis and actinobacillosis in cattle for over a century, and it’s also used to treat sporotrichosis and botryomycosis.
4. It’s used to treat zygomycetes and other fungal infections.
5. It’s also used to treat disorders that affect animals.

Sample Questions

Question 1: What is potassium oxide used for?

Answer: 

It is frequently utilised as a fertiliser in the agriculture industry. Potassium oxide is also utilised in soap production and glass production. Potassium oxide is also known to be involved in some medicinal procedures.

Question 2: Is potassium oxide acidic or basic?

Answer: 

A basic oxide is potassium oxide. FeO (iron oxide) and CaO (calcium oxide) are two other major basic oxides (calcium oxide).

Question 3: What happens when Potassium is Exposed to Air?

Answer: 

During the reaction, three chemicals are formed: potassium oxide, potassium peroxide, and potassium superoxide. In the presence of oxygen, potassium is an extremely active metal that reacts violently. Potassium oxidises more quickly than the majority of metals, forming oxides containing oxygen-oxygen bonds.

8K + 4O₂  → 2K₂O+ 2KO₂ + K₂O₂

Question 4: What is Potassium Hydroxide used for?

Answer: 

In the agricultural industry, it is utilised as a fertiliser. It is water insoluble. This makes it valuable in sectors such as ceramics, glass, and optics. It’s utilised in the production of medications for animal ailments and fungal infections in humans. It’s utilised in the production of soap.

Question 5: How does Potassium Oxide react with Sulphuric Acid?

Answer:

Sulphuric acid interacts with potassium oxide to produce potassium sulphate and water. The reaction’s chemical equation is as follows:

K₂O  +  H₂SO4  →  K₂SO4  +  H₂O