What are Potassium Hexacyanoferrate (II) Salts?

What Exactly is Potassium Hexacyanoferrate (II)?

Potassium Hexacyanoferrate (II) is a yellow inorganic crystalline salt  with the chemical formula of K4[Fe(CN)6].

It is a silvery-white soft metal present in group 1 of the periodic table. It has an atomic number of 19 and it is represented by the symbol (K).

It consists of the following elements 

  1. Potassium
  2. Iron
  3. Carbon, and 
  4. Nitrogen.

IRON 

Iron is a metal that is found in group 8 of the periodic table. It is also one of the most common elements found on earth. It has an atomic number of 26 and is represented by the symbol (Fe). 

CARBON 

Carbon is a nonmetal found in group 14 of the periodic table. It has an  atomic number of 6 and is represented by the symbol (C). 

NITROGEN 

Nitrogen is a colorless, tasteless and odorless gas and the most plentiful element present in the Earth’s atmosphere. It is found in group 15 of the periodic table and is represented with the symbol (N).

POTASSIUM 

Potassium is a mineral that is important for  various functions of the body. It is found in Group 1 (Ia) of the periodic table and is represented with the symbol (K).

Preparation of Potassium Hexacyanoferrate (II) Salts

Potassium Hexacyanoferrate (II) is prepared using hydrogen cyanide, ferrous chloride, and calcium hydroxide compounds. The combination of these compounds are treated with potassium salts to precipitate the mixed calcium potassium salt, which is then treated with potassium carbonate to give tetra potassium salt.

Properties of Potassium Hexacyanoferrate (II)

The following are the properties of Potassium Hexacyanoferrate (II).

Appearance  Potassium Hexacyanoferrate (II) appears as a light yellow crystalline granules.
Name Potassium Hexacyanoferrate (II)
Other Names Yellow Prussiate of Potash, Potassium ferrocyanide
Molecular Weight The molecular weight of Potassium Hexacyanoferrate (II) is 368.35 g/mol.
Solubility  Potassium Hexacyanoferrate (II) is soluble in alcohol, acids and water. 
Density  Potassium Hexacyanoferrate (II) has a density of 1.85 g/cm3.
Melting Point  Potassium Hexacyanoferrate (II) has a melting point of 69   71 °C.
Boiling Point  Potassium Hexacyanoferrate (II) has a boiling point of 400 °C.

Chemical Reactions of Potassium Hexacyanoferrate (II) Salts

Reaction With Sulphuric Acids 

Sulphuric acids react with potassium Hexacyanoferrate (II) to produce potassium sulfate, ferrous sulfate, ammonium sulfate, and carbon monoxide.

Equation of the Reaction 

K4[Fe(CN)6] + 6H2SO4 + 6H2O ⇢ 2K2SO4 + FeSO4 + 3(NH4)2SO4 + 6CO

Reaction With Ferric Chloride 

Ferric Chloride reacts with Potassium Hexacyanoferrate (II) to form a complex compound of Iron (III) potassium Hexacyanoferrate (II) and potassium chloride.

Equation of the Reaction 

K4[Fe(CN)6] + FeCl3 ⇢ KFe[Fe(CN)6] + 3KCl

Decomposition of Potassium Hexacyanoferrate (II)

Potassium cyanide is prepared by decomposing the Potassium Hexacyanoferrate (II). 

Equation of the Reaction 

K4[Fe(CN)6] ⇢  4KCN + FeC2 + N2 

Reaction With Copper Sulfate 

Copper Sulfate reacts with Potassium Hexacyanoferrate (II)  to produce Cupric Ferrocyanide and potassium sulfate.

Equation of the Reaction 

K4[Fe(CN)6] + 2CuSO4 ⇢ Cu2[Fe(CN)6] + K2SO4

Uses of Potassium Hexacyanoferrate (II)

  1. Potassium Hexacyanoferrate (II) can be used as fertilizer in agriculture.
  2. Potassium Hexacyanoferrate is used as an oxidant for catalyst regeneration in hydroxylations.
  3. It is used in electroplating.
  4. Potassium Hexacyanoferrate (II) is used in the production of wine and citric acid.
  5. It is used as an oxidizing agent.
  6. Potassium Hexacyanoferrate (II) is used in the separation of copper from molybdenum ore.
  7. Potassium Hexacyanoferrate (II) is used in the production of iron blue pigments. 
  8. Potassium Hexacyanoferrate (II) is  used in food and pharmaceutical industries for coloring purposes.

Precautions to Take While Handling Potassium Hexacyanoferrate (II)

  1. Use safety goggles with side protection when using Potassium Hexacyanoferrate (II).
  2. Wear suitable gloves when carrying out experiments with Potassium Hexacyanoferrate (II).
  3. Do not eat, drink or smoke when carrying out experiments with Potassium Hexacyanoferrate (II).
  4. Good Hygiene Measures should be observed.
  5. Wash the eyes with running water when in contact with Potassium Hexacyanoferrate (II).
  6. Avoid playing with the Potassium Hexacyanoferrate (II) salts in the lab.
  7. After every experiment, the Potassium Hexacyanoferrate (II) salts should be disposed properly.

FAQ’S

What type of salt is Potassium Hexacyanoferrate (II)?

Potassium Hexacyanoferrate (II) is an inorganic, yellow crystalline salt with the chemical formula of K4[Fe(CN)6]. It is gotten from hydrogen cyanide, ferrous chloride, and calcium hydroxide. Potassium Hexacyanoferrate (II) is also used in the production of iron blue pigments.

What is the nature of Potassium Hexacyanoferrate (II)?

Potassium Hexacyanoferrate (II) is an inorganic compound.