Potassium perchlorate (KClO4) is a compound that contains potassium, chlorine, and oxygen. It is commonly used in pyrotechnics and explosives due to its oxidizing properties.
| IUPAC name | Potassium perchlorate |
| Molecular formula | KClO4 |
| CAS number | 7778-74-7 |
| Synonyms | Percal K, Perchlorate of potash, Potassium chlorate(VII), UN 1489 |
| InChI | InChI=1S/ClHO4.K/c2-1(3,4)5;/h(H,2,3,4,5);/q;+1/p-1 |
Potassium Perchlorate Properties
Potassium Perchlorate Formula
Potassium perchlorate has a chemical formula of KClO4, which indicates that it contains one potassium atom, one chlorine atom, and four oxygen atoms. The compound is an inorganic salt that is highly soluble in water, making it a useful oxidizer in many applications.
Potassium Perchlorate Molar Mass
The molar mass of KClO4 is calculated by adding the atomic masses of the constituent elements in the compound. The atomic masses of potassium, chlorine, and oxygen are 39.10 g/mol, 35.45 g/mol, and 16.00 g/mol, respectively. Thus, the molar mass of KClO4 is 138.55 g/mol.
Potassium Perchlorate Boiling Point
KClO4 does not have a defined boiling point since it decomposes before it reaches a boiling point. When heated to high temperatures, KClO4 decomposes into potassium chloride and oxygen gas. However, it has been observed that the compound can sublimate at temperatures around 400-500 °C.
Potassium Perchlorate Melting Point
The melting point of KClO4 is approximately 610 °C. At this temperature, the solid compound transforms into a liquid state. The high melting point of KClO4 makes it suitable for use in various industrial applications.
Potassium Perchlorate Density g/mL
The density of KClO4 is about 2.52 g/cm³ at room temperature. This indicates that the compound is denser than water, which has a density of 1 g/cm³. The high density of KClO4 makes it an effective oxidizer in pyrotechnics.
Potassium Perchlorate Molecular Weight
The molecular weight of KClO4 is 138.55 g/mol. This value is determined by adding the atomic masses of the constituent elements in the compound. The molecular weight of KClO4 is useful in determining the mass of the compound needed for a particular reaction or process.
Potassium Perchlorate Structure
KClO4 has a tetragonal crystal structure, which means that it has four-fold symmetry about its c-axis. The crystal lattice of the compound is formed by potassium ions, chlorine ions, and oxygen ions, which are held together by ionic bonds.
Potassium Perchlorate Solubility
KClO4 is highly soluble in water, with a solubility of approximately 4.5 g/mL at room temperature. The compound is also soluble in other polar solvents such as ethanol and acetone. However, it is insoluble in nonpolar solvents such as benzene and chloroform. The solubility of KClO4 is an important factor in its use as an oxidizer in various industrial applications.
| Appearance | White crystalline solid |
| Specific gravity | 2.52 |
| Color | White |
| Odor | Odorless |
| Molar mass | 138.55 g/mol |
| Density | 2.52 g/cm³ |
| Melting point | 610 °C |
| Boiling point | Decomposes before boiling point |
| Flash point | Not applicable |
| Water solubility | 4.5 g/mL at 25 °C |
| Solubility | Soluble in ethanol and acetone, insoluble in benzene and chloroform |
| Vapor pressure | Not applicable |
| Vapor density | Not applicable |
| pKa | Not applicable |
| pH | Neutral |
Potassium Perchlorate Safety and Hazards
KClO4 can pose safety hazards if not handled properly. The compound is a strong oxidizer and can react with combustible materials to cause fires or explosions. Inhaling the dust or fumes from KClO4 can also cause irritation to the respiratory system. Prolonged exposure to the compound may lead to skin irritation or dermatitis. When handling KClO4, it is important to use appropriate personal protective equipment such as gloves, safety glasses, and respirators. The compound should also be stored in a cool, dry place away from incompatible materials and sources of heat and ignition.
| Hazard symbols | Oxidizer |
| Safety description | Keep away from combustible materials. Wear appropriate personal protective equipment. Avoid breathing dust or fumes. |
| UN IDs | UN1489 |
| HS code | 2829.90.90 |
| Hazard class | 5.1 – Oxidizing substances |
| Packing group | II |
| Toxicity | May cause skin irritation or dermatitis with prolonged exposure. Ingestion or inhalation of the compound may cause respiratory irritation. |
Potassium Perchlorate Synthesis Methods
One can synthesize KClO4 through a variety of methods.
One common method is through the reaction of potassium chlorate with barium perchlorate. The reaction produces KClO4 and barium chloride as a byproduct, which can be filtered out.
Another method involves the reaction of potassium chlorate with hydrochloric acid and sodium chloride. The reaction produces KClO4 and sodium chlorate, which can be separated through crystallization.
Reaction between potassium hydroxide and ammonium perchlorate can also synthesize KClO4. The reaction produces KClO4 and ammonium hydroxide, which can be separated through filtration.
Another method involves the reaction of potassium chloride with sodium perchlorate in the presence of a catalyst. The reaction produces KClO4 and sodium chloride, which can be separated through crystallization.
Potassium Perchlorate Uses
KClO4 has a variety of uses in different industries. Some of its common uses are:
- Pyrotechnics: A popular oxidizing agent in the pyrotechnics industry. Used in the manufacture of fireworks, flares, and other types of explosives.
- Rocket propellants: Used as an oxidizer in the manufacture of rocket propellants. Commonly used in solid rocket boosters and in space shuttle launches.
- Airbag initiators: Used as an initiator in the manufacture of airbags. To deploy an airbag, one sends an electrical charge through a wire coated with KClO4. This causes a reaction that produces nitrogen gas, which inflates the airbag.
- Matches: Used in the production of safety matches. To produce a combustible compound that ignites upon striking against a rough surface, one mixes it with antimony sulfide and sulfur.
- Electroplating: Used in the electroplating industry as a component in electrolytes used for electroplating metals.
- Medicine: Used in the treatment of thyroid conditions such as hyperthyroidism. However, its use in medicine has decreased due to safety concerns.
- Analytical chemistry: Also used as a reagent in analytical chemistry for the determination of certain substances.
Questions:
Q: What types of bonding are contained in a potassium perchlorate molecule?
A: KClO4 contains both ionic and covalent bonding. The K+ ion and ClO4- ion are held together by ionic bonds, while the perchlorate ion itself contains both covalent and ionic bonds.
Q: What is the formula of potassium perchlorate?
A: KClO4.
Q: Is potassium perchlorate aqueous?
A: KClO4 can dissolve in water, making it aqueous under certain conditions.
Q: What is potassium perchlorate used for?
A: KClO4 has a variety of applications, including use in fireworks, rocket propellants, and airbag inflators. It is also used in analytical chemistry as a reagent and oxidizing agent.
Q: How to make flash powder without potassium perchlorate?
A: Flash powder can be made without KClO4 by using alternative oxidizers, such as ammonium perchlorate, sodium perchlorate, or barium peroxide.
Q: What is the oxidation state of an individual chlorine atom in KClO4?
A: The oxidation state of the individual chlorine atom in KClO4 is +7.
Q: Is KClO4 soluble in water?
A: Yes, KClO4 is soluble in water.
Q: Is KClO4 an acid or base?
A: KClO4 is neither an acid nor a base. It is a salt composed of a metal (potassium) and a polyatomic ion (perchlorate).