The key difference between potassium cyanide and potassium gold cyanide is that potassium cyanide contains potassium cations and cyanide anions, whereas potassium gold cyanide (or potassium dicyanoaurate) contains potassium cations, gold cations, and cyanide anions.
Potassium cyanide is a chemical compound having the chemical formula KCN while Potassium gold cyanide is also known as potassium dicyanoaurate.
CONTENTS
1. Overview and Key Difference
2. What is Potassium Cyanide
3. What is Potassium Gold Cyanide (Potassium Dicyanoaurate)
4. Potassium Cyanide vs Potassium Gold Cyanide in Tabular Form
5. Summary – Potassium Cyanide vs Potassium Gold Cyanide
What is Potassium Cyanide?
Potassium cyanide is a chemical compound having the chemical formula KCN. It appears as a colorless crystalline salt that has a similar appearance to sugar. Moreover, this substance is highly water-soluble. Potassium cyanide has many important applications, especially in gold mining, organic synthesis, and electroplating applications.
Figure 01: Appearance of Potassium Cyanide Crystalline Solid
More importantly, potassium cyanide has high toxicity. This is a moist solid that can emit small quantities of hydrogen cyanide upon hydrolysis. This releases a smell similar to bitter almonds. However, everyone cannot smell this. It is a genetic trait that determines who can identify this smell. Furthermore, the taste of this substance can be given as an acrid, bitter taste having a burning sensation that is similar to lye.
We can produce potassium cyanide by treating the HCN (hydrogen cyanide) with a potassium hydroxide aqueous solution. This reaction has to be followed by the evaporation of the solution in the presence of a vacuum. Typically, the world production of potassium cyanide is about 50,000 tons annually.
When it is in an aqueous solution, this substance can dissociate into potassium cation and cyanide anion. The solid form of KCN has a cubic crystal structure that is similar to the structure of sodium chloride. Each potassium ion is surrounded by six cyanide ions. Although cyanide is diatomic and has less symmetry than chloride in sodium chloride lattice, it can still rotate so rapidly. However, the free rotation is hindered under low temperature and high pressure.
What is Potassium Gold Cyanide (Potassium Dicyanoaurate)?
Potassium gold cyanide is also known as potassium dicyanoaurate. It is an inorganic compound having the chemical formula K[Au(CN)2]. It appears as a colorless or white crystalline solid powder that is usually prepared by dissolving it in metallic gold in the presence of an aqueous solution of potassium cyanide. Often, this substance is used in gold plating techniques.
Figure 02: The Structure of Potassium Gold Cyanide Compound
Typically, the gold content in potassium gold cyanide is about 68.2% gold by weight of the substance. Moreover, this compound is water-soluble and is also highly soluble in alcohol. We can use this substance for the photoreduction of gold ions through the nanopowder ZnO. Besides, it has applications in the preparation of gold-gold junction electrodes in voltammetric glucose detection.
What is the Difference Between Potassium Cyanide and Potassium Gold Cyanide?
Potassium cyanide is a chemical compound having the chemical formula KCN and Potassium gold cyanide is an inorganic compound having the chemical formula K[Au(CN)2]. The key difference between potassium cyanide and potassium gold cyanide is that potassium cyanide contains potassium cations and cyanide anions whereas potassium gold cyanide contains potassium cations, gold cations, and cyanide anions.
The following table summarizes the difference between potassium cyanide and potassium gold cyanide.
Summary – Potassium Cyanide vs Potassium Gold Cyanide
Potassium cyanide and potassium gold cyanide are important compounds. The key difference between potassium cyanide and potassium gold cyanide is that potassium cyanide contains potassium cations and cyanide anions, whereas potassium gold cyanide contains potassium cations, gold cations, and cyanide anions.
Reference:
1. “Potassium Cyanide.” National Center for Biotechnology Information. PubChem Compound Database, U.S. National Library of Medicine.
Image Courtesy:
1. “Kaliumcyanid” By morienus (uploaded by de:Benutzer:BXXXD from de:wiki) – own photo (CC BY-SA 3.0) via Commons Wikimedia
2. “Dicyanoaurate(I)-3D-balls” By Benjah-bmm27 – Own work (Public Domain) via Commons Wikimedia