Isopropanol (Isopropyl alcohol), also known as rubbing alcohol, is a colorless and flammable chemical compound. It is widely used as a solvent, disinfectant, and antiseptic due to its strong and effective properties.
| IUPAC Name | Propan-2-ol |
| Molecular Formula | C3H8O |
| CAS Number | 67-63-0 |
| Synonyms | Isopropyl alcohol, 2-Propanol, sec-propyl alcohol, dimethylcarbinol, IPA, rubbing alcohol |
| InChI | InChI=1S/C3H8O/c1-3(2)4/h3-4H,1-2H3 |
Isopropanol Properties
Isopropyl alcohol Structure
The structure of isopropyl alcohol consists of a propane chain with a hydroxyl group (-OH) attached to the middle carbon atom. The hydroxyl group gives isopropyl alcohol its characteristic properties as an alcohol, including its ability to dissolve in water and act as a solvent for many organic compounds. The presence of a methyl group (-CH3) on the first carbon atom of the propane chain gives isopropyl alcohol its unique properties, including its relatively low boiling and melting points.
Isopropyl alcohol Molar Mass
The molar mass of isopropyl alcohol, also known as rubbing alcohol, is 60.1 g/mol. Molar mass is the mass of one mole of a substance, which is the amount of a substance that contains the same number of entities as there are atoms in 12 grams of carbon-12. In the case of isopropyl alcohol, one mole of the substance contains 60.1 grams. The molar mass is an important parameter in many chemical calculations, including determining the amount of a substance needed for a reaction or the concentration of a solution.
Isopropyl alcohol Boiling Point
The boiling point of isopropyl alcohol is 82.6 °C (180.7 °F) at atmospheric pressure. The boiling point is the temperature at which a substance changes from a liquid to a gas, and it is a physical property that is determined by the intermolecular forces of the substance. Isopropyl alcohol has a relatively low boiling point compared to other alcohols, such as ethanol, due to its small size and the presence of a methyl group.
Isopropyl alcohol Melting Point
The melting point of isopropyl alcohol is -89 °C (-128.2 °F). The melting point is the temperature at which a substance changes from a solid to a liquid, and it is also a physical property that is determined by the intermolecular forces of the substance. Isopropyl alcohol has a relatively low melting point compared to other alcohols due to its small size and the presence of a methyl group.
Isopropyl alcohol Density g/mL
The density of isopropyl alcohol is 0.786 g/mL at room temperature (20 °C or 68 °F). Density is the mass of a substance per unit volume, and it is a physical property that is determined by the atomic and molecular structure of the substance. Isopropyl alcohol has a lower density than water, which has a density of 1 g/mL at room temperature.
Isopropyl alcohol Molecular Weight
The molecular weight of isopropyl alcohol is 60.1 g/mol. Molecular weight is the sum of the atomic weights of all the atoms in a molecule, and it is a characteristic property of the substance. Isopropyl alcohol has a relatively small molecular weight compared to other alcohols, such as ethanol, which has a molecular weight of 46.1 g/mol.
Isopropyl alcohol Formula
The chemical formula for isopropyl alcohol is C3H8O. This formula represents the number and types of atoms that make up the molecule of isopropyl alcohol. The formula shows that isopropyl alcohol contains three carbon atoms, eight hydrogen atoms, and one oxygen atom. This formula is useful for determining the molecular weight and other physical and chemical properties of isopropyl alcohol.
| Appearance | Clear, colorless liquid |
| Specific Gravity | 0.786 g/mL at 20 °C |
| Color | Colorless |
| Odor | Characteristic, alcoholic |
| Molar Mass | 60.1 g/mol |
| Density | 0.786 g/mL at 20 °C |
| Melting Point | -89 °C (-128.2 °F) |
| Boiling Point | 82.6 °C (180.7 °F) at atmospheric pressure |
| Flash Point | 12.2 °C (54 °F) |
| Water Solubility | Completely miscible |
| Solubility | Miscible with organic solvents |
| Vapor Pressure | 33.8 mmHg at 20 °C |
| Vapor Density | 2.07 (air = 1) |
| pKa | 16.5 |
| pH | 7 (neutral) |
Isopropanol Safety and Hazards
Isopropanol is a highly flammable and volatile liquid with a low flash point and should be handled with care. It can cause skin and eye irritation, and prolonged or repeated exposure can lead to dryness and cracking of the skin. Isopropanol can also cause respiratory irritation and dizziness if inhaled, and ingestion can result in nausea, vomiting, and abdominal pain. It is important to use appropriate protective equipment such as gloves, goggles, and a respirator when working with isopropanol. Storage should be in a cool, dry, and well-ventilated area away from heat sources and incompatible materials.
| Hazard Symbols | F, Xi |
| Safety Description | Highly flammable liquid and vapor. Causes serious eye irritation. Causes skin irritation. Harmful if swallowed. Suspected of causing genetic defects. Suspected of damaging fertility or the unborn child. May cause drowsiness or dizziness. |
| UN Ids | UN1219 |
| HS Code | 2905.12.0000 |
| Hazard Class | 3 |
| Packing Group | II |
| Toxicity | LD50 (oral, rat): 5,630 mg/kg |
Isopropanol Synthesis Methods
Isopropanol, also known as isopropyl alcohol, can be synthesized through a variety of methods.
One common method involves the hydration of propylene using a catalyst such as sulfuric acid or phosphoric acid. The process involves the reaction of propylene with water in the presence of the catalyst to produce isopropanol and diisopropyl ether as a byproduct.
Another method involves the hydrogenation of acetone using a catalyst such as copper chromite or nickel. The process utilizes hydrogen gas and the catalyst to reduce acetone to isopropanol.
Certain strains of bacteria can produce isopropanol through the fermentation of carbohydrates, such as corn or sugar cane. The process includes converting carbohydrates into glucose, which is then fermented by the bacteria to yield isopropanol.
Another method of synthesizing isopropanol involves the reaction of a Grignard reagent with formaldehyde, followed by acid-catalyzed hydrolysis. This method is particularly useful for producing isopropanol with a high degree of purity.
Regardless of the method used, the resulting isopropanol must be purified through distillation or other methods to remove any impurities and achieve the desired level of purity.
Isopropanol Uses
Isopropanol, also known as isopropyl alcohol, has numerous uses in various industries and applications. Some of the common uses of isopropanol are:
- Solvent: Effective solvent for a variety of substances, including oils, resins, and gums. Used as a solvent in manufacturing coatings, inks, and adhesives.
- Disinfectant: Used as a disinfectant in healthcare facilities, laboratories, and other settings. It is effective against many pathogens, including bacteria, viruses, and fungi.
- Antiseptic: Used as an antiseptic in various topical applications, such as hand sanitizers and disinfectant wipes. Also used in the preparation of the skin for medical procedures.
- Cleaning agent: Used in various cleaning applications, such as cleaning electronic components, optical lenses, and precision instruments.
- Fuel: Used as a fuel additive in gasoline and diesel engines. It is also used as fuel in some racing cars.
- Extraction agent: Used as an extraction agent in the production of essential oils, flavors, and fragrances.
- Chemical intermediate: Used as a chemical intermediate in the production of various chemicals, such as acetone, isopropyl acetate, and glycerol.
Questions:
Q: Is isopropyl alcohol polar?
A: Yes, isopropyl alcohol is a polar molecule. It has a hydroxyl (-OH) group attached to a chain of three carbon atoms, which makes it a polar molecule. This polarity makes it a good solvent for many substances.
Q: Is isopropyl alcohol the same as rubbing alcohol?
A: Rubbing alcohol is a type of alcohol that is made from isopropyl alcohol or ethanol. Isopropyl alcohol is one of the main ingredients in rubbing alcohol, along with water and other compounds. So, while isopropyl alcohol is not exactly the same as rubbing alcohol, it is a key component of rubbing alcohol.
Q: Where to buy isopropyl alcohol?
A: Isopropyl alcohol can be purchased from a variety of sources, including drug stores, grocery stores, and online retailers. It is commonly sold in concentrations ranging from 70% to 99%, with the 70% concentration being the most common. It is important to note that due to high demand and shortages, isopropyl alcohol may be difficult to find in some areas.