Ferric chloride is a chemical compound, also known as iron (III) chloride, with the chemical formula FeCl3. It is a dark brown or reddish-brown crystalline solid and is highly soluble in water. 

Ferric chloride is a common industrial chemical used in a wide variety of applications, such as wastewater treatment, etching and engraving metals, and as a reagent in organic synthesis.

It is highly corrosive and causes skin and eye irritation, so it must be handled with care and proper protective equipment.

Ferric chloride boiling point

Ferric chloride (FeCl3) has a boiling point of 315 °C (599 °F) at standard atmospheric pressure. The boiling point of ferric chloride can vary depending on factors such as pressure and concentration. 

Additionally, ferric chloride is usually used as a solution rather than as a pure substance, and the boiling point of a solution depends on the concentration of the solution.

Ferric Chloride Solution Preparation

To prepare ferric chloride solution, solid ferric chloride (FeCl3) is dissolved in water. The amount of ferric chloride required and the concentration of the solution depend on the intended use of the solution.

For example, for use in water treatment, solutions with a concentration of 10–40% FeCl3 are used, while in the laboratory, lower concentrations of 1–2% FeCl3 are used.

Procedure for Preparing Ferric Chloride Solution

Materials

Solid ferric chloride

Distilled water

Glass stirring rod

Glass container or beaker

Measuring device (such as a graduated cylinder or pipette)

Procedure

Take up the amount of ferric chloride required depending on the desired concentration of the solution. 

For example, to prepare a 10% solution of ferric chloride, a quantity of 10 grams of solid ferric chloride is taken for every 100 ml of water.

Pour the required amount of solid ferric chloride into a glass container or beaker.

Slowly add distilled water to the container while stirring with a glass rod. Water is added in small amounts until all the solid ferric chloride is dissolved.

Keep stirring the solution until it is well mixed and homogeneous.

Label the container with the concentration and date of preparation and store the solution in a dry place.

Ferric Chloride Uses

Ferric chloride (FeCl3) has industrial, laboratory and environmental uses. Some of the most common uses of ferric chloride are as follows:

1. Ferric chloride is a coagulating agent. It is used in the treatment of drinking water and waste water. This is done to remove bacteria, viruses and heavy metals from the water.

2. It is used in the production of printed circuit boards, electronic components, and other metal-based products.

3. It is used as a catalyst in chemical reactions.

4. It is used as a pickling agent in the production of steel

5. It is used in the treatment of anemia and other blood disorders. It is also used as a coagulant in blood tests.

6. It is used to remove stains, discoloration, and other forms of damage.

7. It is used in dyeing and printing of textiles.

8. It is used as a catalyst in the production of polymers including PVC and phenolic resins.

9. Ferric chloride is used in the refining of crude oil to remove sulfur compounds and other impurities.

10. It is used in nuclear fuel reprocessing.

Ferric chloride has a myriad of applications, highlighting its importance as a chemical in many different industries and sectors.

Ferric Chloride Test for Phenol

The ferric chloride test is a commonly used chemical test to detect the presence of phenol in a given sample. Phenols are organic compounds containing a hydroxyl (-OH) group attached to an aromatic ring.

Materials

Ferric chloride solution (FeCl3)

Sample to be tested

Test tube

Dropper or pipette

Procedure

Take a test tube and put a few drops of the sample to be tested in it in a clean test tube.

Add a few drops of ferric chloride solution to the test tube with the help of a dropper or pipette.

Observe the color change of the solution. A positive test will be a deep purple color, while a negative test will have no color change or a pale yellow color.

The ferric chloride test works by forming a complex between phenol and the ferric ion (Fe3+), which produces a purple color. The intensity of the color is proportional to the concentration of phenol in the sample.

Methylamine in Water Reacts with Ferric Chloride

Methylamine (CH3NH2) is a weak base and does not react with ferric chloride (FeCl3) under normal conditions. If methylamine is present in water as a salt, such as methylammonium chloride (CH3NH3Cl), it reacts with ferric chloride.

Reaction between methylammonium chloride and ferric chloride.

FeCl3 + 3 CH3NH3Cl → Fe(CH3NH3)3Cl3 + 3 HCl

In this reaction, ferric chloride reacts with three molecules of methylammonium chloride to form a complex salt called ferric methylammonium chloride, with hydrochloric acid (HCl) being formed as a byproduct.

The reaction can be detected by the formation of a dark green or brown color in the solution, indicating the formation of a ferric methylammonium chloride complex.