Ammonium Dichromate: General, Physical, Chemical Properties, Uses, FAQs

Ammonium dichromate is an inorganic compound. It is flammable in nature . It has the chemical formula (NH4)2Cr2O7. Ammonium dichromate is an orange-red needle formed during crystallization. Toxic chemical salts are used to sensitize organic emulsions such as gelatin to the hardening effects of actinic radiation. It is very sensitive to light. Let's see the name of ammonium dichromate -diammonium dichromate ammonium bichromate; ammonium pyrochromate.

General properties of ammonium dichromate- (NH4)2Cr2O7

• Ammonium dichromate has a density of 2.12 g/cm³.

• Ammonium dichromate has a molecular weight of 252.07 g/mol.

• Ammonium dichromate has a spontaneous ignition temperature of 190 °C.

• The melting point of ammonium dichromate is 180 °C.

• The chemical formula for ammonium dichromate is (NH4)2Cr2O7.

Physical Properties of Ammonium Dichromate- (NH4)2Cr2O7

• Odorless

• Its appearance is an orange-red crystal.

• Stable under recommended storage conditions.

• Ammonium dichromate has a specific gravity of 2.1500.

• It is not soluble in acetone.

• It is soluble in alcohol.

Chemical Properties of Ammonium Dichromate- (NH4)2Cr2O7

At room temperature and pressure, it is an orange acidic crystal, soluble in water and alcohol. Ammonium dichromate decomposes on heating to produce chromium(III) oxide and nitrogen gas.

Uses of Ammonium Dichromate- (NH4)2Cr2O7

• Ammonium dichromate sensitizes solutions that are used in lithography.

• It has it’s application in pyrotechnics, lithography and photoengraving.

• It is used as a magnetic recording material.

• It has it’s application as an approved pesticide .

• It is a mordant for dyeing.

• It has it’s application as a pigment.

Hazards and Safety of Ammonium Dichromate- (NH4)2Cr2O7

The main hazards of Ammonium Dichromate are:

• Toxic

• Oxidising

• Dangerous for environment

• Mutagen

Safety precautions must be taken to deal with these hazards.

Safety: Like all chromium (VI) compounds, ammonium dichromate is highly toxic and explosive under certain conditions.

Safety precautions should be taken when using ammonium dichromate.

Wear safety glasses and avoid skin contact with ammonium dichromate (wear gloves).

Oxidation Reactions- (NH4)2Cr2O7

Ammonium dichromate acts as an oxidizing agent. Often reacts violently with reducing agents. The greater the influence of the reducing agent, the more violent the reaction. This compound is also used in the oxidation of fatty alcohols. It is used for the corresponding aldehydes and ketones in ZrCl4/wet SiO2 under solvent-free conditions. This occurs at relatively high yields.Reaction: Consists of tabletop volcano and pyrolysis.When a small pile of ammonium dichromate is ignited with a few drops of ethanol, it can be seen that a spark is generated and an ash-like product is formed. This phenomenon resembles a volcanic eruption.