[Chemistry Class Notes] on Potassium Chlorate Pdf for Exam

Potassium Chlorate is an inorganic compound which contains one atom of potassium, three atoms of oxygen and one atom of chlorine elements. It appears as white crystalline powder at room temperature in its pure form. It is also called pot crate and also known by its trade names Fegabit or Fekabit. It was discovered by French Chemist Claude Louis Berthollet in the end of the 18th century. At that time, it was mainly used in fireworks but due to safety reasons the role of Potassium Chlorate in fireworks is almost over. Presently, Potassium Chlorate is banned for use in fireworks in most of the countries.

What is the Chemical Formula of Potassium Chlorate? 

Molecular formula of Potassium Chlorate is KClO3. It has cation of potassium and anion of chlorate which is shown below in its structural formula as well. 

Properties of Potassium Chlorate 

Potassium Chlorate has following physical and chemical properties –

• In its pure form, it is a white crystalline solid. 

• Its molar mass is 122.55 g/mol.

• Its density is 2.32 g/cm3.

• Its melting point is 356℃.

• Its boiling point is 400℃.

• It is soluble in water. As the temperature increases, solubility of Potassium Chlorate in water also increases. 

• It is soluble in glycerol as well. 

• It is slightly soluble in acetone and liquid ammonia as well. 

• Its oxidizing properties make it suitable for ignition. 

• It is hygroscopic. 

• Its crystal structure is monoclinic. 

• Potassium Chlorate immediately decomposes if heated in the presence of a catalyst such as MnO2. Reaction is given below –

2KClO3(s) ? 3O2(g) + 2KCl(s)

4KClO3 ? 3KClO4 + KCl

On further heating potassium perchlorate decomposes into oxygen and Potassium Chloride. Reaction is as follows –

KClO4 ? KCl + 2O2

Preparation of Potassium Chlorate 

It is the most common chlorate used in industries. Due to its various uses, it is produced in the industries at large scale. For its large – scale production Liebig process is used in the industries. 

Liebig Process – In this process Potassium Chlorate is produced by passing chlorine into hot calcium hydroxide and then adding Potassium Chloride in it. Reactions involved are given below –

6Ca(OH)2 + 6Cl2 ? Ca(ClO3)2 + 5CaCl2 + 6H2O

Ca(ClO3)2 + 2KCl ? 2KClO3 + CaCl2

Other methods of preparation of Potassium Chlorate are as follows –

Electrolysis Method – Potassium Chlorate can also be produced by electrolysis of Potassium Chloride. In this method, we take anode of carbon, platinum or mixed metal oxide and cathode of titanium. Both the electrodes are inserted in the aqueous solution of Potassium Chloride and a current is passed through. As the reaction progresses, Potassium Chlorate precipitates out. After the electrolysis, you can easily obtain the crystals or precipitate of Potassium Chlorate by removing the electrodes from the cell and then filter the cell contents. 

Disproportionation Method – For production of Potassium Chlorate in small amounts, a disproportionation method is used. In this method, sodium chloride and sodium chlorate are formed by disproportionation of sodium hypochlorite. Then sodium chlorate undergoes metathesis reaction with Potassium Chloride. Reactions involved are given below 

3NaOCl(aq) ? 2NaCl(s) + NaClO3(aq)

KCl(aq) + NaClO3(aq) ? NaCl(aq) + KClO3(s)

Caustic Potash – Potassium Chlorate can also be produced by passing chlorine gas into a hot solution of potassium hydroxide. Reaction is given below –

3Cl2(g) + 6KOH(aq) ? KClO3(aq) + 5KCl(aq) + 3H2O(l)

Uses of Potassium Chlorate 

Initially, Potassium Chlorate was used in the fireworks industry to give beautiful colors to the fireworks. As it is a strong oxidizing agent, it produces oxygen on decomposition. This helps in the combustion of fireworks. This high amount of heat excites the electrons and they produce beautiful colors in the firework mixture.  But soon Potassium Chlorate was used in various illegal activities due its explosive properties. So, presently use of Potassium Chlorate in fireworks is banned in many countries. Apart from this application, it has various other uses. Few of them are listed below –

• It is used as an oxidizing agent. 

• It is used in the preparation of oxygen. 

• It can be used as a disinfectant. 

• It is used in safety matches in a very small amount. 

• It is used in explosives. 

• It helps in early arrival of the blossoming stage of longan trees. Thus, causing it to produce fruit in the warmer climate. 

• It is used in firearms and percussion caps.

• It is used in propellants.

• It is used in combination with silver fulminate in trick noise makers such as snappers, pop – its, bang – snaps etc. 

• It is used in pyrotechnics. 

• It is used in smoke grenades. 

• It is used in laboratories as well. 

• It is used in chlorate candles or oxygen candles. 

• It is used in oxygen supply systems of aircrafts, space stations and submarines etc.  

• It is used in limelights (A type of stage lighting which was used in theaters and music halls in old time) as well. 

• It is also used as a pesticide. 

• Molten Potassium Chlorate is used in dramatic screaming jelly babies, Gummy bear, Haribo and Trolli candy etc. 

Potassium Chlorate has many applications and is a very useful chemical for many industries, but its explosive or oxidizing properties are being used in illegal and inhuman activities. It is used in Afghanistan for production of improvised explosive devices which are used in many inhuman activities. It was the main ingredient in the car bomb used in 2002 Bali (Thailand) bombings that killed 202 people.  

This ends our coverage on the topic “Potassium Chlorate”. We hope you enjoyed learning and were able to grasp the concepts. We hope after reading this article you will be able to solve problems based on the topic and will handle Potassium Chlorate carefully in the lab. If you are looking for solutions to NCERT Textbook problems based on this topic, then log on to the website or download the Learning App. By doing so, you will be able to access free PDFs of NCERT Solutions as well as Revision notes, Mock Tests and much more.