Glycerin or glycerol or glycerine is a clear, colorless, odorless, and sweet-tasting liquid that is widely used as a solvent, sweetener, and humectant in food, pharmaceutical, and personal care products.
| IUPAC Name | Propane-1,2,3-triol |
| Molecular Formula | C3H8O3 |
| CAS number | 56-81-5 |
| Synonyms | 1,2,3-Propanetriol; Glycerol; Glycerine; Glycyl alcohol; Glyrol |
| InChI | InChI=1S/C3H8O3/c1-2-3(4)5/h2-5,2H,1H2/t3-/m0/s1 |
Glycerol Properties
Glycerol Structure
Glycerol has a simple, triatomic structure composed of a carbon atom, three hydroxyl groups, and three hydrogen atoms. The molecule is symmetrical, with the hydroxyl groups evenly spaced around the central carbon atom.
Glycerin Molar Mass
The molar mass of glycerin is 92.09 g/mol. It is an important value in determining the quantity of glycerin present in a sample, and it can be used to calculate the number of moles in a sample.
Glycerin Formula
The chemical formula of glycerin is C3H8O3. The molecule consists of three carbon atoms, eight hydrogen atoms, and three oxygen atoms.
Glycerin Molecule
Glycerin is a trihydric alcohol, meaning it contains three hydroxyl groups (-OH) in its molecular structure. These hydroxyl groups give glycerin its unique solubility and reactivity properties, making it useful in a variety of applications, including food, pharmaceuticals, and personal care products.
Glycerin Boiling Point
The boiling point of glycerin is 290°C. This high boiling point is a result of the strong hydrogen bonding between glycerin molecules, which requires a large amount of energy to overcome.
Glycerin Melting Point
The melting point of glycerin is 17.8°C. At this temperature, glycerin transitions from a solid to a liquid state.
Glycerin Density g/ml
The density of glycerin is 1.26 g/ml. This value can be used to calculate the volume occupied by a given mass of glycerin.
Glycerin Molecular Weight
The molecular weight of glycerin is 92.09 g/mol. This value is important in determining the amount of glycerin present in a sample.
| Appearance | Clear, colorless liquid |
| Specific Gravity | 1.26 g/cm3 |
| Color | Colorless |
| Odor | Odorless |
| Molar Mass | 92.09 g/mol |
| Density | 1.26 g/cm3 |
| Melting Point | 17.8°C |
| Boiling Point | 290°C |
| Flash Point | 140°F (60°C) |
| Water Solubility | Soluble |
| Solubility | Soluble in water, ethanol, and propylene glycol |
| Vapor Pressure | Not applicable |
| Vapor Density | Not applicable |
| pKa | 11.4 |
| pH | 7 (neutral) |
Glycerin Safety and Hazards
Glycerin is generally considered safe for use as a food additive and in personal care products. However, it can be irritating to the skin and eyes, and ingestion of large amounts can cause gastrointestinal distress. It is flammable and should be stored away from heat sources and flames. It is also toxic to certain aquatic organisms, so care should be taken to avoid environmental contamination.
| Hazard Symbols | Flam. Liq. 2, Irritant |
| Safety Description | S16, S24/25 |
| UN IDs | UN 1170, Class III |
| HS Code | 2905.45.00 |
| Hazard Class | 3 |
| Packing Group | II |
| Toxicity | LD50 (oral, rat) = 2900 mg/kg |
Glycerin Synthesis Methods
Glycerol can be synthesized through a variety of methods, including the hydration of propene, the reduction of epichlorohydrin, and the transesterification of triglycerides. The most commonly used method of synthesizing glycerin is the saponification of triglycerides, which involves the hydrolysis of fats and oils with an alkaline catalyst. The resulting mixture is then purified to obtain pure glycerin. Another method involves the reaction of allyl alcohol with chlorine, followed by hydrolysis to yield glycerin. Regardless of the method used, the final product must be purified to remove impurities and ensure its quality for use in various applications.
Glycerin Uses
Glycerin has a wide range of uses, including as a component in the production of personal care products such as soaps, creams, and lotions, and as a food additive. It is also used as a solvent, a sweetener, a humectant, and an emulsifier in the food industry. In the pharmaceutical industry, it is used as a component in the manufacture of some medicines, including cough syrups and liquid medications. Glycerin is also used in the production of explosive materials and as a component in antifreeze solutions. In the cosmetic industry, glycerin is used as a moisturizing agent, due to its ability to retain water and keep the skin hydrated. It is also used as a component in the production of biofuels, such as biodiesel, and in the synthesis of other chemicals.
Questions:
What is glycerol?
Glycerol is a colorless, odorless, sweet-tasting, viscous liquid that is widely used in the food, pharmaceutical, and personal care industries. It is also known as glycerin, glycerine, or 1,2,3-propanetriol. It is a triol, a type of alcohol consisting of three hydroxyl (OH) groups, and is an important component of many naturally occurring lipids, such as triglycerides, phospholipids, and glycolipids. In addition to its use as a component in various products, glycerol has a variety of applications as a solvent, a sweetener, a humectant, and an emulsifier.
Is glycerol a lipid?
Yes, glycerol is a lipid. Lipids are a diverse group of biomolecules that include fats, oils, waxes, and steroids. Glycerol is an important component of many naturally occurring lipids, such as triglycerides, phospholipids, and glycolipids. Triglycerides, also known as triacylglycerols, are the most abundant form of lipids in the human body and in the diets of many animals. They are composed of three fatty acids esterified to a glycerol molecule, and they serve as an important source of energy. In addition to its role as a component of lipids, glycerol also has a variety of uses in the food, pharmaceutical, and personal care industries.
What kind of lipid forms when a glycerol combines with fatty acids through dehydration synthesis?
When a glycerol molecule combines with three fatty acids through a process called dehydration synthesis, a triglyceride lipid is formed. Triglycerides, also known as triacylglycerols, are the most abundant form of lipids in the human body and in the diets of many animals. They are composed of three fatty acids esterified to a glycerol molecule, and they serve as an important source of energy. The formation of a triglyceride occurs through the removal of a molecule of water (H2O) from each fatty acid and glycerol, resulting in the formation of an ester bond between the fatty acid and the glycerol. This process is the reverse of hydrolysis, which breaks down triglycerides into their component fatty acids and glycerol.
Is glycerol a carbohydrate?
No, glycerol is not a carbohydrate. Carbohydrates are a class of biomolecules that include sugars, starches, and fibers, and are an important source of energy for the body. They are characterized by their composition of carbon (C), hydrogen (H), and oxygen (O) atoms, and their general formula is (CH2O)n. Glycerol, on the other hand, is a type of alcohol consisting of three hydroxyl (OH) groups and has the molecular formula C3H8O3. While glycerol is not a carbohydrate, it is an important component of many naturally occurring lipids, such as triglycerides, phospholipids, and glycolipids.
Is glycerol polar?
Yes, glycerol is polar. Polar molecules have a positive and negative end due to the uneven distribution of electrons, resulting in a dipole moment. This polarity allows polar molecules to form hydrogen bonds with other polar molecules, making them more soluble in polar solvents such as water. Glycerol, being a triol with three hydroxyl (OH) groups, is polar due to the presence of three polar hydroxyl groups, which are strong hydrogen bond donors. This polarity is an important factor in its various applications, including as a solvent, a sweetener, a humectant, and an emulsifier.
What is glycerin?
Glycerol, also known as glycerin, serves as a solvent, sweetener, humectant, and emulsifier due to its colorless, odorless, sweet-tasting, and viscous liquid form. It is a triol with three hydroxyl (OH) groups and has the molecular formula C3H8O3. Glycerin is an important component of many naturally occurring lipids, such as triglycerides, phospholipids, and glycolipids. In addition, it is a byproduct of the production of biodiesel, soap, and many other products, making it a widely available and cost-effective ingredient. Its high viscosity and sweet taste make it a common ingredient in many food and personal care products, and its ability to retain moisture makes it a popular ingredient in cosmetics and skincare products.
Where to buy glycerin?
One can purchase glycerin at many different types of stores, including:
- Pharmacies: Many pharmacies carry glycerin, often in the form of a topical product for skin care or as an ingredient in other personal care items.
- Health food stores: Some health food stores carry glycerin, often as a food-grade product for use in cooking and baking.
- Online retailers: There are many online retailers that sell glycerin, including Amazon, eBay, and Walmart, among others.
- Chemical suppliers: For larger quantities or for industrial use, glycerin can be purchased from chemical suppliers, such as Sigma-Aldrich, Fisher Scientific, and VWR International.
- Home improvement stores: Some home improvement stores carry glycerin for use in home projects, such as DIY soap-making.
It is important to note that the quality and purity of glycerin can vary depending on the source and intended use, so it is important to check the product specifications before purchasing.
What is vegetable glycerin?
Vegetable glycerin, also known as glycerol or glycerine, derives from vegetable oils such as palm oil, soybean oil, or coconut oil and is a byproduct of biodiesel production. Its colorless, odorless, and sweet-tasting liquid form makes it a popular choice as a food additive, sweetener, humectant, and emulsifier. With a molecular formula of C3H8O3, vegetable glycerin consists of three hydroxyl (OH) groups and is considered non-toxic and non-irritating. This ingredient finds widespread use in the food, cosmetic, and pharmaceutical industries. As a moisturizing ingredient in skincare products, a sweetener in food and beverage products, and a solvent in e-cigarette production, vegetable glycerin proves versatile and effective.
Glycerol 3 phosphate?
Glycerol 3-phosphate (G3P) is a derivative of glycerol that contains a phosphoryl group. It is a molecule that plays an important role in cellular metabolism, particularly in the breakdown and storage of glucose, known as glycolysis. G3P regulates glucose and fatty acid metabolism and controls cellular processes such as gene expression, protein synthesis, and cell division. It can also be converted into glucose or other sugars through gluconeogenesis and can be used as a substrate for the synthesis of triacylglycerols, the primary lipid storage form in animals and plants. Deficiencies in the metabolic pathways that involve G3P can result in various diseases and disorders, such as diabetes, obesity, and liver diseases.