Calcium peroxide (CaO2) is a chemical compound that releases oxygen when in contact with water. It is commonly used as an oxidizing agent in industrial and agricultural applications, including soil remediation and wastewater treatment.
| IUPAC Name | Calcium dioxide |
| Molecular Formula | CaO2 |
| CAS Number | 1305-79-9 |
| Synonyms | Calcium superoxide; Calcium dioxide peroxide; CP |
| InChI | InChI=1S/Ca.O2/c;1-2/q+2;-2 |
Calcium Peroxide Properties
Calcium Peroxide Formula
The chemical formula of calcium peroxide is CaO2, which indicates that the compound contains one calcium atom and two oxygen atoms. The formula is a representation of the compound’s composition and is useful in determining the molar mass and other properties of the substance. Calcium peroxide is commonly used as an oxidizing agent in various industrial and agricultural applications, including soil remediation, wastewater treatment, and the production of oxygen gas.
Calcium Peroxide Molar Mass
The molar mass of calcium peroxide, which is represented by the chemical formula CaO2, is 72.077 g/mol. Molar mass is the mass of one mole of a substance, and it is commonly used to convert between mass and moles in chemical reactions. Knowing the molar mass of CaO2 is useful in determining the amount of the substance needed for a particular reaction.
Calcium Peroxide Boiling Point
CaO2 is a solid compound and does not have a boiling point in the traditional sense. Instead, it undergoes thermal decomposition when heated, releasing oxygen gas and leaving behind calcium oxide. This process occurs at temperatures above 150°C (302°F).
Calcium Peroxide Melting Point
The melting point of CaO2, which is the temperature at which it transitions from a solid to a liquid state, is approximately 350°C (662°F). This high melting point is due to the strong ionic bonds between the calcium and oxygen atoms in the compound.
Calcium Peroxide Density g/mL
The density of CaO2 is 2.91 g/mL. Density is a measure of the amount of mass per unit volume, and it is useful in determining the amount of space a substance occupies.
Calcium Peroxide Molecular Weight
The molecular weight of CaO2 is 72.077 g/mol. This value is calculated by adding up the atomic weights of all the atoms in the chemical formula of CaO2.
Calcium Peroxide Structure
CaO2 has a crystal structure in which each calcium ion is surrounded by six oxygen atoms. The oxygen atoms are arranged in a tetrahedral geometry around the calcium ion, with each oxygen forming a covalent bond with the calcium ion. The compound has a white or yellowish color and is insoluble in water.
| Appearance | White powder |
| Specific gravity | 2.91 g/cm³ |
| Color | White or yellowish |
| Odor | Odorless |
| Molar Mass | 72.077 g/mol |
| Density | 2.91 g/mL |
| Melting Point | ~350°C (662°F) |
| Boiling Point | Decomposes above 150°C (302°F) |
| Flash Point | N/A |
| Water solubility | Insoluble |
| Solubility | Insoluble in organic solvents |
| Vapor pressure | N/A |
| Vapor density | N/A |
| pKa | N/A |
| pH | N/A |
Calcium Peroxide Safety and Hazards
CaO2 poses several potential hazards and safety concerns. It is an oxidizing agent and may cause fires or explosions when in contact with organic materials, such as oils or fuels. In addition, it may react violently with certain acids, such as hydrochloric acid. Contact with the eyes, skin, or respiratory system may cause irritation, and ingestion or inhalation may cause more severe health effects. It is important to handle CaO2 with care and follow appropriate safety procedures, including wearing protective clothing and eyewear and working in a well-ventilated area.
| Hazard symbols | Oxidizing agent, Irritant |
| Safety Description | Avoid contact with organic materials, Wear protective clothing and eyewear, Work in a well-ventilated area |
| UN IDs | UN1457 |
| HS Code | 2825.90.90 |
| Hazard Class | 5.1 (Oxidizing agents) |
| Packing Group | III |
| Toxicity | May cause irritation upon contact with eyes, skin, or respiratory system. May cause more severe health effects upon ingestion or inhalation. |
Calcium Peroxide Synthesis Methods
A variety of methods can synthesize CaO2.
One common method involves the reaction of CaO with hydrogen peroxide in the presence of water. Another method involves the reaction of Ca(OH)2 with hydrogen peroxide. In both cases, the resulting product is CaO2 and water.
Another method involves the reaction of Ca(OH)2 with sodium peroxide. This produces CaO2 and sodium hydroxide.
The reaction between CaCl2 and sodium peroxide is also familiar. This produces CaO2 and sodium chloride.
In a laboratory setting, CaO2 can also be produced through the reaction of calcium metal with oxygen gas. However, this method is not practical for large-scale production due to the high cost of calcium metal.
Calcium Peroxide Uses
CaO2 has a range of uses across several industries. Here are some of the most common applications:
- Agriculture: Used as an oxygen source in soil remediation and as a crop preservative.
- Environmental remediation: Used to enhance the bioremediation of contaminated soil and water by providing a slow release of oxygen.
- Food industry: Used as a food additive to improve dough quality and to bleach flour.
- Chemical synthesis: Used in the production of various chemicals, including H2O2 and calcium stearate.
- Polymer production: Used as a polymer initiator in the production of polyethylene and other plastics.
- Water treatment: Used as a source of hydrogen peroxide for water treatment, including disinfection and odor control.
- Mining: Used as a blasting agent in mining operations.
- Oil and gas industry: Used as a source of oxygen for enhanced oil recovery and in the removal of sulfides and mercaptans from oil and gas streams.
Questions:
Q: Can hydrogen peroxide dissolve calcium deposits in the human body?
A: Hydrogen peroxide may be effective at breaking down Ca2+ deposits in some cases, but it should only be used under the guidance of a healthcare professional.
Q: Where did calcium peroxide come from?
A: CaO2 was first discovered in the early 1900s by a French chemist named Paul Sabatier.
Q: What is calcium peroxide?
A: CaO2 is a white or yellowish powder that is used as a source of oxygen in various industrial and environmental applications.
Q: Is calcium peroxide salt?
A: No, CaO2 is not a salt. It is a chemical compound that contains calcium, oxygen, and sometimes other elements.
Q: What is CaO2?
A: CaO2 is the chemical formula for calcium peroxide.
Q: What does CaO2 stand for?
A: CaO2 is an abbreviation for the chemical compound calcium peroxide.