Potassium cyanide is a highly toxic compound. It is used in industrial applications and can cause severe harm if ingested. Extreme caution should be exercised when handling it.
| IUPAC Name | Potassium cyanide |
| Molecular Formula | KCN |
| CAS Number | 151-50-8 |
| Synonyms | Cyanide of Potassium, Potassium Salt of Hydrocyanic Acid |
| InChI | InChI=1S/CN.K/c1-2;/q-1;+1 |
Potassium Cyanide Properties
Potassium Cyanide Formula
The chemical formula of potassium cyanide is KCN. It consists of one K atom bonded to a CN ion. The formula represents the ratio of atoms in a molecule of KCN.
Potassium Cyanide Molar Mass
The molar mass of KCN is calculated by adding the atomic masses of its constituent elements. K has an atomic mass of 39.10 g/mol, while CN has a combined atomic mass of 26.01 g/mol. Therefore, the molar mass of KCN is 65.11 g/mol.
Potassium Cyanide Boiling Point
KCN has a high boiling point of approximately 1,634 degrees Celsius (2,963 degrees Fahrenheit). This temperature indicates the point at which the liquid form of KCN transforms into a gas.
Potassium Cyanide Melting Point
The melting point of KCN is around 634 degrees Celsius (1,173 degrees Fahrenheit). This temperature represents the transition from its solid state to a liquid state.
Potassium Cyanide Density g/mL
The density of KCN is approximately 1.52 g/mL. This measurement indicates the mass of the substance per unit volume, with higher density indicating greater mass in a given volume.
Potassium Cyanide Molecular Weight
The molecular weight of KCN, also known as its molar mass, is 65.11 g/mol. This value represents the sum of the atomic masses of all the atoms in a molecule of KCN.
Potassium Cyanide Structure
The structure of KCN consists of a K+ cation and a CN- anion. The K+ ion is positively charged, while the CN- ion carries a negative charge. They are held together by ionic bonds.
Potassium Cyanide Solubility
KCN is highly soluble in water. It readily dissolves in water, forming a colorless solution. This property makes it easier to handle and use in various industrial applications. However, its solubility also means that caution must be exercised when handling it.
| Appearance | White crystalline solid |
| Specific Gravity | 1.52 g/mL |
| Color | Colorless |
| Odor | Odorless |
| Molar Mass | 65.11 g/mol |
| Density | 1.52 g/mL |
| Melting Point | 634 degrees Celsius (1,173 degrees Fahrenheit) |
| Boiling Point | 1,634 degrees Celsius (2,963 degrees Fahrenheit) |
| Flash Point | Not applicable |
| Water Solubility | Highly soluble |
| Solubility | Soluble in water |
| Vapour Pressure | Not applicable |
| Vapour Density | Not applicable |
| pKa | Not applicable |
| pH | Basic (alkaline) |
Potassium Cyanide Safety and Hazards
KCN poses significant safety hazards and must be handled with extreme caution. It is highly toxic if ingested, inhaled, or absorbed through the skin. Direct contact with KCN can cause severe burns and irritation. It releases toxic HCN gas when exposed to acids or heated. Adequate ventilation and personal protective equipment, such as gloves and goggles, are crucial when working with this compound. Storage should be in a secure, well-ventilated area, away from incompatible substances. In case of exposure or ingestion, immediate medical attention is essential. KCN’s hazards necessitate strict adherence to safety protocols to minimize risks to human health and the environment.
| Hazard Symbols | Skull and crossbones, Corrosive |
| Safety Description | Highly toxic, Corrosive, Dangerous for the environment |
| UN IDs | UN1680, UN1585 |
| HS Code | 2837.11.00 |
| Hazard Class | 6.1 (Toxic substances), 8 (Corrosive substances) |
| Packing Group | PG II |
| Toxicity | Extremely toxic |
Potassium Cyanide Synthesis Methods
Various methods enable the synthesis of KCN.
In one common method, KCN synthesis involves bubbling a solution of HCN gas into a solution of potassium hydroxide (KOH). The reaction between the two compounds generates KCN and water as a byproduct.
In this method, potassium carbonate (K2CO3) reacts with NH4CN when they are mixed together and heated. As a result, the reaction produces KCN, ammonia gas, and carbon dioxide.
To obtain KCN, one can react with potassium chloride (KCl) with NaCN, resulting in the exchange of ions between the compounds. This process leads to the formation of KCN and sodium chloride (NaCl).
Professionals who possess expertise in handling hazardous materials and have implemented the necessary safety precautions should exclusively conduct the synthesis of KCN. Due to the extreme toxicity of KCN, strict adherence to proper laboratory practices and protocols is crucial to ensure the safety of the individuals involved and to prevent any potential environmental risks.
Potassium Cyanide Uses
KCN has various uses across different industries. Here are some of its applications:
- Gold Mining: Gold mining companies commonly use KCN to extract gold from ore. They mix it with the ore to form a soluble complex that separates gold from other minerals.
- Chemical Industry: The chemical industry employs KCN as a precursor to produce various chemicals, including organic cyanides, adiponitrile, and potassium ferrocyanide. Manufacturers utilize these compounds in the production of pharmaceuticals, dyes, and pigments.
- Metal Plating: KCN plays a crucial role in electroplating processes, providing a smooth and adherent metal coating on surfaces. It is particularly effective in plating silver and zinc.
- Analytical Chemistry: Analytical laboratories utilize KCN as a reagent for various analytical techniques. It finds application in titration reactions and serves as a source of cyanide ions in complexometric titrations.
- Pest Control: In some cases, KCN acts as a rodenticide to control rodent populations. However, strict regulations govern its use due to its extremely toxic nature.
- Fumigation: KCN serves as an effective fumigant for eradicating pests in stored grains, ship cargo, and structures due to its high toxicity, ensuring efficient pest control.
- Photography: Historically, the photography industry employed KCN for developing and fixing black and white films. However, due to safety concerns, alternative chemicals have become widely prevalent in the industry.
It is essential to note that the use of KCN requires strict adherence to safety protocols and regulations due to its highly toxic nature.
Questions:
Q: How to make potassium cyanide?
A: The synthesis of KCN involves various methods, including reacting KOH with HCN or K2CO3 with ammonium cyanide (NH4CN).
Q: What is potassium cyanide?
A: Itis a highly toxic compound with the chemical formula KCN. It is a white crystalline solid used in gold mining, chemical manufacturing, and other industrial applications.
Q: Where to buy potassium cyanide in Thailand?
A: It is illegal and highly dangerous to purchase or possess KCN without proper authorization or legitimate scientific purposes.
Q: Does cyanide inhibit the sodium-potassium pump?
A: Yes, cyanide inhibits the Na-K pump, disrupting cellular processes and leading to severe toxicity.
Q: How to make potassium gold cyanide?
A: K[Au(CN)₂] is produced by dissolving gold in a solution containing KCN. The process involves electroplating or reaction with KCN in the presence of oxygen.
Q: Is potassium cyanide in rat poison?
A: KCN is not typically used in commercial rat poisons. Other compounds, such as anticoagulants or zinc phosphide, are commonly employed for rodent control.
Q: What is the taste of potassium cyanide?
A: KCN is described as having a bitter almond-like taste. However, it is highly toxic, and ingestion can be lethal even in small amounts.
Q: Is potassium cyanide poisonous?
A: Yes, KCN is extremely poisonous. It inhibits cellular respiration, leading to tissue damage, organ failure, and potentially death.
Q: Can I buy potassium cyanide in the UK?
A: The purchase, possession, or sale of KCN without proper authorization or legitimate scientific purposes is illegal and highly regulated in the UK.
Q: What does potassium cyanide cause?
A: KCN can cause severe toxicity, leading to symptoms such as difficulty breathing, dizziness, nausea, seizures, and, in high doses, rapid death.
Q: Where to get potassium cyanide?
A: The acquisition of KCN is restricted and strictly regulated. It is primarily available through authorized chemical suppliers for legitimate scientific, industrial, and research purposes.