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Potassium Cyanide

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Potassium Cyanide - A Form of Cyanide

Potassium cyanide is a chemical compound with the formula KCN. This colorless crystalline salt, which will be similar in appearance to sugar, and is highly soluble in water. Most KCN is used in gold mining, organic synthesis, and electroplating. Smaller applications in our daily lives include making jewelry for chemical gilding and buffing.

Chemistry is really important and efficient for the research and study of living organisms because it helps students and scientists to understand the life processes of every living thing on earth at the molecular level. At any molecular level, every process of life takes place due to the involvement of various minor or major chemical reactions.


Thus, it is important for the students to learn their chapters well and understand all the chemistry concepts by practicing with a maximum number of past years’ question papers and sample question papers available on the Vedantu website. This will help them to understand the time management skill and learn the marking schemes that carry maximum marks and plan which question needs what type of answers. Break down larger portions into smaller effective points and write them down in a separate notebook so it will help you in revising before the exams. Make note of the important questions that keep repeating in the recent past year question papers and give more weightage to those questions and prepare a little extra because it might repeat in the current year also. If you have any doubts about the equations and chemical formulations that are taught during the classes then try to spend some extra time in the lab and get to understand all the concepts by trying out the experiments and practicing them really well. This will definitely help you write your formulas and equations really well.

More About Potassium Cyanide

A compound named potassium cyanide is a colorless crystalline salt, similar to sugar particles in its appearance. Its general formula is KCN and IUPAC's name is Potassium Cyanide. Potassium Cyanide is a very poisonous inorganic salt. Potassium Cyanide is a highly toxic substance in nature and exposure to this element can be very much lethal for humans. Apart from all these circumstances, it is considered to be highly soluble in water. Mostly it is used in the gold mining industries for the extraction of gold and silver ores. It is also used in various other industries for electroplating, fumigation, chemical gilding, and buffing.

Structure of Potassium Cyanide

Chemical Formula is KCN.


The molecular formula is KCN.


The molar mass of potassium cyanide is 65.12 g/mol.


Potassium cyanide is a compound formed of potassium( K+ cation ) and Cyanide (CN- anion). In which potassium is positively charged and cyanide is negatively charged ions. Carbon has a triple bond with the nitrogen ion. It is similar to the structure of NaCl crystalline solid.

Properties of Potassium Cyanide

Potassium Cyanide is a white crystalline colorless solid.


Its density is 1.52 g/ml.


Its melting point is 634.5’c


Potassium cyanide is highly soluble in water.


It decomposes slowly in the air and rapidly after heating.


Potassium Cyanide, when reacted with hydrogen peroxide, forms a less harmful cyanide derivative.


KCN+ H2O2 -> KOCN+ H2O


It is a toxic substance. It tastes bitter and it exhibits burning sensations.

Preparation of Potassium Cyanide

Potassium Cyanide can be prepared by various methods in industries as per their use. The most commonly used methods are:


When hydrogen cyanide is reacted with an aqueous solution of potassium hydroxide:-


HCN + KOH -> KCN + H₂O 


When Formamide is reacted with KOH:-


HCONH2 + KOH -> KCN + 2H2O

Uses of Potassium Cyanide

Potassium Cyanide and Sodium Cyanide are widely used for the production of nitriles and carboxylic acids.


Potassium Cyanide was produced for the decomposition of potassium ferrocyanide. It was produced before the invention of the Castner process.


In the colloidal process, KCN is used as a photographic fixer.


It is used in the gold mining procedure, where KCN forms water-soluble Potassium gold cyanide and Potassium Hydroxide in the presence of oxygen.


4Au+ 8KCN +O2 +2 H2O -> 4KAu(CN)2 + 4KOH


KCN is used in mining industries of gold and other metals.


Potassium cyanide is used for the preparation of plastic and another organic synthesis.

It is used for electroplating and fumigation.


Potassium Cyanide is also used in warehouses.


It is also used as an insecticide by farmers.

KCN

Potassium cyanide is a highly toxic inorganic substance with the general formula KCN. It is generally prepared by the reaction of hydrogen cyanide (HCN) and potassium hydroxide (KOH). This is made up of a solid base (KOH) and a weak acid (HCN).  This is used for the extraction of gold, silver, and other metals. It is one of the forms of cyanide prepared for the decomposition of potassium ferrocyanide before the invention of the Castner process.


Potassium Cyanide is harmful to health. If someone inhales this element then they may face severe health problems which can even lead to death. A person may also suffer from headaches, vomiting, dizziness, and seizures which can be harmful to human health.


Potassium cyanide is a salt prepared with the help of hydrogen cyanide or a reagent formamide.

FAQs on Potassium Cyanide

1. What are the Harmful Effects of Potassium Cyanide?

Potassium cyanide is a harmful toxic substance and is very much similar to the crystalline solid of NaCl in appearance. 

  • It's toxic in many cases and high exposure to Potassium Cyanide can lead to headaches, nausea, dizziness, anxiety, and heart racing.

  • It can also lead to death in severe cases.

  • In some cases, if a person is suffering from any kind of chronic symptoms then eventually they will suffer from headache, nausea, vomiting or bright red flush if they come in contact with Potassium Cyanide

  • On the other hand, if a person is suffering from any kind of acute symptoms then he/she may face difficulty in breathing or either they may suffer from seizure or cardiac arrest.

  • According to sources of chemistry, it's said that even a single spoon of this toxic element can kill approximately 43% of the total population.

2.How can we Prepare Potassium Cyanide?

Potassium Cyanide can be prepared by various methods in the industries. Potassium cyanide was prepared for the decomposition of potassium ferrocyanide and was invented before the Castner process. There are many different methods among which the most commonly used method of preparing Potassium Cyanide is given below :

  • Hydrogen Cyanide reacts with Potassium Hydroxide which leads to the formation of Potassium Cyanide and Water.

HCN + KOH -> KCN + H₂O

Here in this method, there is a relation between a strong base (KOH) and a weak acid (HCN) which leads to the formation of potassium salt (KCN). 

  • Another method of preparing potassium cyanide is with formamide,

HCONH₂ + KOH -> KCN + H₂O

Here in this reaction, a crystalline salt is prepared with the combination of a strong base and weak acid.

3. What happens if you touch cyanide?

Cyanide is poisonous in nature when you try to consume but apart from causing acute poisoning, cyanide can cause some allergic reactions to the skin due to the irritant and poisonous nature of cyanide and thus causing an irritant over skin, and thus dermatitis termed potassium cyanide allergies as cyanide rash, which is characterized by itching, vesiculation and disruption of the skin as seen in our case.

4. Do apples have cyanide?

Actually there is a portion of cyanide in apple seeds but you're highly unlikely to manage to eat that much apple seeds to poison yourself, so you can rest easy if you occasionally swallow one as that will not put you life in danger. Apples contain a compound called amygdalin in their seeds, which is a combination of cyanide-and-sugar based molecules. The apples or apple seeds can then decompose and produce the poisonous gas hydrogen cyanide.

5. Is potassium cyanide and sodium cyanide the same?

The key difference between sodium cyanide and potassium cyanide is that sodium cyanide is produced via treating hydrogen cyanide with sodium hydroxide, whereas potassium cyanide is produced via treating hydrogen cyanide with potassium hydroxide. When coming to its default nature both the cyanides are highly toxic due to the same reason of high reactivity in them. Sodium cyanide is an inorganic compound having the chemical formula NaCN and potassium cyanide  is an inorganic compound as well having the chemical formula KCN.

6. What are the Harmful Effects of Potassium Cyanide?

Potassium cyanide is a harmful toxic substance and is very much similar to the crystalline solid of NaCl in appearance. 

It's toxic in many cases and high exposure to Potassium Cyanide can lead to headaches, nausea, dizziness, anxiety, and heart racing.

It can also lead to death in severe cases.

In some cases, if a person is suffering from any kind of chronic symptoms then eventually they will suffer from headache, nausea, vomiting or bright red flush if they come in contact with Potassium Cyanide

On the other hand, if a person is suffering from any kind of acute symptoms then he/she may face difficulty in breathing or either they may suffer from seizure or cardiac arrest.

According to sources of chemistry, it's said that even a single spoon of this toxic element can kill approximately 43% of the total population. 

7. How can we Prepare Potassium Cyanide?

Potassium Cyanide can be prepared by various methods in the industries. Potassium cyanide was prepared for the decomposition of potassium ferrocyanide and was invented before the Castner process. There are many different methods among which the most commonly used method of preparing Potassium Cyanide is given below :

Hydrogen Cyanide reacts with Potassium Hydroxide which leads to the formation of Potassium Cyanide and Water.

HCN + KOH -> KCN + H2O

Here in this method, there is a relation between a strong base (KOH) and a weak acid (HCN) which leads to the formation of potassium salt (KCN). 

Another method of preparing potassium cyanide is with formamide,

HCONH2 + KOH -> KCN + H2O

Here in this reaction, a crystalline salt is prepared with the combination of a strong base and weak acid.