What is the Difference Between Anhydrous and Monohydrate Citric Acid?

The main difference between anhydrous and monohydrate citric acid lies in the presence of water. Anhydrous citric acid has no water of crystallization, while monohydrate citric acid has one water molecule linked with each citric acid molecule.

The chemical formula of anhydrous citric acid is C6H8O7, and its molecular mass is 192.12 g/mol. It is produced through crystallization from hot water. Anhydrous citric acid is used in various industries, such as the pharmaceutical industry as a stabilizer and preservative, and as a flavoring agent in beverages, food, and other items.

On the other hand, the chemical formula of monohydrate citric acid is C6H8O7·H2O, and its molecular mass is 210.138 g/mol. It is produced through crystallization from cold water. Monohydrate citric acid is also used in the food and beverage industries, as well as in detergents.

In summary:

Anhydrous citric acid has no water of crystallization.
Monohydrate citric acid has one water molecule linked with each citric acid molecule.
Anhydrous citric acid is used in various industries, including pharmaceuticals and food.
Monohydrate citric acid is also used in the food and beverage industries, as well as in detergents.

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What is the Difference Between Anhydrous and Monohydrate Citric Acid?

Comparative Table: Anhydrous vs Monohydrate Citric Acid

The main difference between anhydrous and monohydrate citric acid lies in the presence of water. Anhydrous citric acid has no water of crystallization, while monohydrate citric acid has a water molecule associated with one citric acid molecule. Here is a comparison table highlighting the differences between the two forms:

Property	Anhydrous Citric Acid	Monohydrate Citric Acid
Chemical Formula	C6H8O7	C6H8O7.H2O
Molar Mass	192.12 g/mol	210.138 g/mol
Production	Crystallization from hot water	Crystallization from cold water
Water Content	No water of crystallization	One water molecule per citric acid molecule
Melting Point	153°C (1013 hPa)	135°C
Density	1.665 g/cm³ (20°C)	1.50 g/cm³ (20°C)

Anhydrous citric acid is produced via crystallization from hot water, while monohydrate citric acid is produced via crystallization from cold water. Anhydrous citric acid can be converted to the monohydrate form at about 78°C. Both forms of citric acid have various applications, such as acidity regulators, flavoring agents, and chelating agents in the food industry.

Guilherme Mazui

Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.