Hydrogen peroxide or H2O2 is a pale blue liquid with strong oxidizing properties. It’s commonly used as a disinfectant, bleaching agent, and in rocketry as a propellant. In high concentrations, it can be harmful.
| IUPAC Name | Dihydrogen dioxide |
| Molecular Formula | H2O2 |
| CAS Number | 7722-84-1 |
| Synonyms | Hydrogen dioxide, Peroxide, Oxydol, Superoxol, Hydronium dioxide, Peroxaan, Asepticper, etc. |
| InChI | InChI=1S/H2O2/c1-2/h1-2H |
Hydrogen Peroxide Properties
H2O2 Structure
Hydrogen peroxide has a bent molecular structure, with an angle of approximately 104.5 degrees between the two oxygen atoms. The molecule has two O-H bonds and one O-O bond. The O-O bond is weak and easily broken, which makes hydrogen peroxide a powerful oxidizing agent. The bent structure of hydrogen peroxide results from the repulsion between the lone pairs of electrons on the oxygen atoms.
Hydrogen Peroxide Formula
The chemical formula of hydrogen peroxide is H2O2, which indicates that each molecule of hydrogen peroxide contains two hydrogen atoms and two oxygen atoms. The formula is a concise way of representing the molecular composition of a substance. The chemical formula of hydrogen peroxide is important for understanding its properties and reactions with other substances.
Hydrogen Peroxide Molar Mass
Hydrogen peroxide has a molar mass of approximately 34.01 g/mol. The molar mass is the sum of the atomic masses of all the atoms in one molecule of the compound. Hydrogen peroxide has two hydrogen atoms and two oxygen atoms in each molecule, so its molar mass is calculated by adding the atomic mass of each atom. The molar mass is an important property of a substance as it is used in stoichiometry calculations to determine the amount of substance present in a given sample.
Hydrogen Peroxide Boiling Point
The boiling point of hydrogen peroxide is 150.2 °C (302.4 °F). This temperature is the point at which the vapor pressure of the liquid is equal to the atmospheric pressure. Above this temperature, the liquid changes into a gas, and below this temperature, it remains in its liquid state. The boiling point of hydrogen peroxide is higher than that of water, which boils at 100 °C, due to the presence of intermolecular hydrogen bonds in hydrogen peroxide.
Hydrogen Peroxide Melting Point
The melting point of hydrogen peroxide is -0.43 °C (31.23 °F). This temperature is the point at which the solid and liquid states of a substance are in equilibrium. At this temperature, the solid form of hydrogen peroxide melts into a liquid. The melting point of hydrogen peroxide is lower than that of water, which melts at 0 °C, due to the unstable nature of the hydrogen peroxide molecule.
Hydrogen Peroxide Density g/mL
The density of hydrogen peroxide is 1.11 g/mL at standard temperature and pressure (STP). This means that one milliliter of hydrogen peroxide weighs 1.11 grams. The density of hydrogen peroxide is higher than that of water, which has a density of 1 g/mL, due to the presence of the heavier oxygen atoms in hydrogen peroxide.
Hydrogen Peroxide Molecular Weight
The molecular weight of hydrogen peroxide is 34.01 g/mol. This value is calculated by adding the atomic masses of each atom in one molecule of hydrogen peroxide. The molecular weight is an important property of a substance as it is used in various calculations, including determining the concentration of hydrogen peroxide in a solution.
| Appearance | Clear, colorless liquid |
| Specific Gravity | 1.11 g/cm3 at 20 °C |
| Color | Pale blue (pure form) |
| Odor | Almost odorless (pure form) |
| Molar Mass | 34.01 g/mol |
| Density | 1.11 g/mL at 20 °C |
| Melting Point | -0.43 °C |
| Boiling Point | 150.2 °C |
| Flash Point | Not applicable |
| Water Solubility | Completely miscible with water |
| Solubility | Soluble in alcohol, ether, and other organic solvents |
| Vapour Pressure | 23.3 mmHg at 20 °C |
| Vapour Density | 1.1 (air = 1) |
| pKa | 11.6 (at 25 °C) |
| pH | 4.5 – 6.0 (10% solution) |
Note: These values are typical values and may vary depending on the purity, concentration, and other factors.
Hydrogen Peroxide Safety and Hazards
Hydrogen peroxide can be hazardous if handled improperly. It is a strong oxidizing agent that can react violently with organic and inorganic substances, potentially causing fire or explosion. The concentrated form of hydrogen peroxide is also corrosive and can cause severe burns or tissue damage upon contact with skin or eyes. Inhaling hydrogen peroxide vapors can irritate the respiratory tract, and ingesting it can cause severe internal damage or even death. Therefore, appropriate safety precautions, such as wearing protective clothing and gloves, avoiding contact with incompatible substances, and using it in a well-ventilated area, must be taken while handling hydrogen peroxide.
| Hazard Symbols | O, C |
| Safety Description | Keep away from heat, sparks, and flames. Wear protective clothing and gloves. Avoid contact with skin, eyes, and clothing. Do not breathe vapors. In case of fire, use water spray, foam, dry chemical, or carbon dioxide. |
| UN IDs | UN2015 |
| HS Code | 2847.00.00 |
| Hazard Class | 5.1 |
| Packing Group | II |
| Toxicity | Toxic if ingested or inhaled. Causes severe skin burns and eye damage. May cause respiratory irritation. May cause fire or explosion. |
Hydrogen Peroxide Synthesis Methods
Hydrogen peroxide can be synthesized by various methods, including the anthraquinone process, the autoxidation of 2-ethylanthrahydroquinone, and the electrolysis of dilute sulfuric acid. The most common method for commercial production of hydrogen peroxide is the anthraquinone process.
In the anthraquinone process, anthraquinone is first hydrogenated to form anthrahydroquinone, which is then oxidized with air in the presence of a catalyst to produce hydrogen peroxide. The hydrogen peroxide is then extracted and purified using various techniques, such as distillation and filtration.
Another method for synthesizing hydrogen peroxide is the autoxidation of 2-ethylanthrahydroquinone. In this method, 2-ethylanthrahydroquinone is exposed to air in the presence of an alkali catalyst, which promotes the autoxidation of the compound to produce hydrogen peroxide.
Electrolysis of dilute sulfuric acid is another method for synthesizing hydrogen peroxide. In this method, dilute sulfuric acid is electrolyzed using a special electrolytic cell, which generates hydrogen peroxide at one of the electrodes.
Hydrogen peroxide can also be synthesized by other methods, such as direct synthesis from hydrogen and oxygen or reduction of peroxides with reducing agents. However, these methods are not commonly used for commercial production of hydrogen peroxide due to their low efficiency and safety concerns.
Hydrogen Peroxide Uses
Hydrogen peroxide is a versatile chemical compound with a wide range of applications across various industries. Here are some common uses of hydrogen peroxide:
- The textile, paper, and pulp industries commonly use H2O2 as a bleaching agent to remove color from fabrics and pulp.
- Healthcare settings use H2O2 as an effective disinfectant to kill bacteria, viruses, and fungi and to sterilize medical equipment and surfaces.
- Water treatment facilities use H2O2 to remove impurities such as iron and manganese and to disinfect water.
- Hair dyes and teeth whitening products use H2O2 to lighten the color of hair and teeth.
- The aerospace industry uses H2O2 as a rocket propellant.
- The production of various polymers, such as polypropylene, polyethylene, and polystyrene, involves the use of H2O2.
- H2O2 is a useful cleaning agent for removing stains and grime from surfaces and cleaning contact lenses.
- H2O2 is used in the food industry as a bleaching agent and preservative for food products.
Overall, H2O2’s versatility makes it a valuable chemical compound with numerous applications in various industries.
Questions:
Hydrogen peroxide price
The price of hydrogen peroxide can vary widely depending on various factors such as the purity, concentration, and quantity purchased. In general, the price of hydrogen peroxide can range from a few cents per pound for technical-grade hydrogen peroxide to several dollars per pound for high-purity grades used in specialized applications.
As of February 2023, the average price of 35% food-grade hydrogen peroxide is around $20 to $30 per gallon or $0.10 to $0.20 per fluid ounce. Industrial-grade hydrogen peroxide with lower purity and concentration can cost less, typically in the range of $1 to $5 per gallon. However, prices may vary depending on the supplier, region, and other factors.
Where to buy hydrogen peroxide?
Hydrogen peroxide is a common chemical compound that can be purchased from a variety of suppliers, both online and in physical stores. Here are some places where you can buy hydrogen peroxide:
- Chemical suppliers: Chemical suppliers, such as Sigma-Aldrich, Fisher Scientific, and VWR International, offer a wide range of grades and concentrations of hydrogen peroxide for various applications.
- Online marketplaces: Online marketplaces, such as Amazon, eBay, and Alibaba, offer hydrogen peroxide from various suppliers with different grades and concentrations.
- Grocery stores and pharmacies: Many grocery stores and pharmacies sell low-concentration hydrogen peroxide (3% to 6%) as an antiseptic for wound cleaning and first aid.
- Pool supply stores: Hydrogen peroxide can be used as a pool and spa oxidizer to maintain water clarity and disinfection. Pool supply stores, such as Leslie’s Pool Supplies, may carry hydrogen peroxide products for this purpose.