Potassium Stearate | Solubility of Things

Identification

Molecular formula

C₁₈H₃₅KO₂

CAS number

593-29-3

IUPAC name

potassium;octadecanoate

State

Potassium stearate is a solid at room temperature. It remains stable under normal conditions and does not volatilize easily.

Melting point (Celsius)

215.00

Melting point (Kelvin)

488.15

Boiling point (Celsius)

350.00

Boiling point (Kelvin)

623.15

General information

Molecular weight

322.54g/mol

Molar mass

322.5360g/mol

Density

1.0280g/cm³

Appearence

Potassium stearate is typically a white, powdery solid. It may also appear as a granular or crystalline powder with a soapy texture. When pressed, it often forms a dull, chalky surface.

Comment on solubility

Solubility of Potassium Octadecanoate

Potassium octadecanoate, or potassium stearate, is a fatty acid salt with the formula C₁₈H₃₆KO₂. Its solubility characteristics are quite noteworthy:

Solubility in Water: Potassium octadecanoate exhibits limited solubility in cold water. The long hydrocarbon chain of the fatty acid reduces the interaction with water molecules, resulting in its less-than-ideal dissolution.
Solubility in Organic Solvents: This compound is more soluble in organic solvents, particularly in non-polar solvents due to its hydrophobic characteristics. Typical solvents include:

Hexane
Chloroform
Benzene

Temperature Effect: As temperature increases, the solubility of potassium octadecanoate in water may slightly improve, but it remains significantly lower compared to its solubility in organic mediums.

In summary, potassium octadecanoate's solubility is influenced largely by its long hydrocarbon chain, which promotes stability in non-polar environments while making it less favored in aqueous solutions. As noted, "the polarity of the solvent greatly influences the extent of solubility," a principle that holds true for this compound.

Interesting facts

Interesting Facts about Potassium Octadecanoate

Potassium octadecanoate, commonly known as potassium stearate, is a fascinating chemical compound that belongs to the class of fatty acid salts. Here are several intriguing aspects of this compound:

Nature of the Compound: As a salt derived from stearic acid, it features a long hydrophobic hydrocarbon tail and a hydrophilic head, making it a surfactant.
Applications: This compound finds a variety of uses, including:

In the cosmetics industry for emulsifying and stabilizing creams and lotions.
As a food additive, primarily as an emulsifier to improve texture and shelf-life of products.
In the manufacturing of soaps and detergents for its cleansing properties.

Biocompatibility: Potassium octadecanoate is often regarded for its biocompatibility, making it suitable for use in biomedical applications, including drug delivery systems.
Research Significance: Studies have shown its potential in enhancing the *permeability* of cellular membranes in pharmaceuticals.
Environmental Impact: As a biodegradable surfactant, potassium octadecanoate presents a lower environmental risk compared to synthetic surfactants.

In summary, potassium octadecanoate is more than just a simple chemical compound; its unique properties and diverse applications underline the intricate relationship between chemistry and various industries. Whether in beauty products, food items, or scientific research, its versatility continues to pique the curiosity of scientists and students alike!