What Is Barium? Barium, a chemical element belonging to the alkaline earth metals, holds significant importance in various fields. At WHAT.EDU.VN, we aim to provide clear and accessible answers to your questions. This article delves into the definition of barium, its properties, diverse applications, and benefits, all while addressing common questions and concerns. Barium compounds, barium uses, alkaline earth metals, and other relevant terms will be explored.
1. What is Barium? A Comprehensive Overview
Barium (Ba) is a chemical element with atomic number 56, situated in Group 2 (also known as the alkaline earth metals) of the periodic table. It is a soft, silvery-white metal that readily reacts with air and water.
1.1 Discovery and History
The story of barium began in 1774 when Carl Wilhelm Scheele identified a new base, barium oxide (BaO), within pyrolusite. Johan Gottlieb Gahn later recognized barium sulfate (BaSO4) as a component of the mineral barite. Intriguingly, a specific barite crystal near Bologna, Italy, exhibited phosphorescence after heating, captivating scientists like Galileo. However, it wasn’t until 1808, with the advent of the electric battery, that Sir Humphry Davy successfully isolated barium through electrolysis. This journey highlights the element’s long-standing presence in scientific inquiry.
1.2 Properties of Barium
- Atomic Number: 56
- Atomic Mass: 137.327 amu (atomic mass units)
- State at Room Temperature: Solid
- Melting Point: 727 °C (1,341 °F)
- Boiling Point: 1,805 °C (3,281 °F)
- Density: 3.51 g/cm³ (at 20 °C, or 68 °F)
- Appearance: Silvery-white (tarnishes quickly in air)
- Electron Configuration: [Xe] 6s²
- Oxidation State: +2
- Electronegativity: 0.89 (Pauling scale)
- Reactivity: Highly reactive
1.3 Barium Isotopes
Naturally occurring barium is composed of six stable isotopes: barium-138 (71.7%), barium-137 (11.2%), barium-136 (7.8%), barium-135 (6.6%), barium-134 (2.4%), and barium-132 (0.10%). Barium-130 (0.11%) is also naturally occurring but undergoes decay by double electron capture with an extremely long half-life (more than 4 × 10^21 years). Over 30 radioactive isotopes of barium are known, with mass numbers ranging from 114 to 153. Barium-133 (half-life of 10.5 years) is used as a gamma-ray reference source.
1.4 Where is Barium Found?
Barium is never found in its pure form in nature due to its high reactivity. It exists in combined forms, primarily as the minerals barite (barium sulfate, BaSO4) and witherite (barium carbonate, BaCO3). Large deposits of barite are found worldwide, with China being the leading producer. Other significant sources include India, the United States, and Morocco. Its presence is noted as comprising approximately 0.03% of the Earth’s crust.
2. Common Uses of Barium and Its Compounds
Barium and its compounds find applications in various industries, including medicine, oil and gas, and manufacturing.
2.1 Medical Applications
Barium sulfate (BaSO4) is a crucial component in medical imaging, particularly X-rays of the gastrointestinal (GI) tract.
- Barium Swallow/Meal: Patients drink a barium sulfate suspension, which coats the esophagus, stomach, and intestines, allowing doctors to visualize these organs on X-rays. This helps in diagnosing conditions such as ulcers, tumors, and swallowing difficulties.
- Barium Enema: Barium sulfate is administered rectally to coat the colon, enabling the detection of polyps, tumors, and other abnormalities.
2.2 Oil and Gas Industry
Barium sulfate is a key component of drilling muds used in oil and gas extraction.
- Drilling Muds: Barium sulfate’s high density increases the density of drilling mud, which helps to:
- Control pressure within the well.
- Lubricate the drill bit.
- Carry rock cuttings to the surface.
- Prevent the well from collapsing.
2.3 Manufacturing and Industrial Applications
Barium compounds are also used in the production of various materials:
- Glass Manufacturing: Barium carbonate (BaCO3) is added to glass to increase its refractive index, making it sparkle. It also enhances the glass’s resistance to scratching and improves its clarity.
- Ceramics: Barium carbonate is used as a flux in the production of ceramics, lowering the melting point of the mixture and facilitating the formation of a smooth, glossy finish.
- Pigments: Barium sulfate is used as a pigment in paints and coatings, providing a bright white color and improving opacity. It is also used as a filler in paper and rubber products.
- Electronics: Barium titanate (BaTiO3) is a ferroelectric material used in capacitors and other electronic components.
- Metallurgy: Barium is used as a getter in vacuum tubes to remove unwanted gases. It is also used as a deoxidizer in copper refining.
- Fireworks: Barium compounds, such as barium nitrate and barium chlorate, produce a green color in fireworks and flares.
3. Benefits of Using Barium Compounds
The widespread use of barium compounds stems from their unique properties, offering several benefits across different applications.
3.1 Enhanced Medical Diagnostics
Barium sulfate’s opacity to X-rays allows for clear visualization of the GI tract, enabling accurate diagnosis of various medical conditions. Early detection and treatment can significantly improve patient outcomes.
3.2 Efficient Oil and Gas Extraction
Barium sulfate’s role in drilling muds ensures safer and more efficient oil and gas extraction, contributing to energy production. Its density helps maintain wellbore stability and prevents blowouts, protecting workers and the environment.
3.3 Improved Material Properties
The addition of barium compounds enhances the properties of various materials, leading to improved performance and durability.
- Glass: Increased refractive index, scratch resistance, and clarity.
- Ceramics: Lower melting point, smooth finish, and improved strength.
- Paints and Coatings: Bright white color, opacity, and durability.
3.4 Other Benefits
- Barium compounds contribute to the brilliance and color effects in pyrotechnics.
- They play a role in specialty applications such as radiation shielding.
4. Potential Risks and Safety Precautions
While barium compounds offer numerous benefits, it’s important to acknowledge potential risks and take necessary safety precautions.
4.1 Toxicity
Soluble barium compounds are toxic to mammals. They can interfere with potassium ion channels, disrupting nerve and muscle function. Ingestion of large amounts of soluble barium salts can lead to severe health problems, including:
- Muscle weakness and paralysis
- Irregular heartbeat
- Breathing difficulties
- Gastrointestinal problems
4.2 Exposure Routes
Exposure to barium compounds can occur through:
- Ingestion: Accidental consumption of contaminated food or water.
- Inhalation: Breathing in barium-containing dust or fumes.
- Skin Contact: Contact with barium compounds can cause irritation.
4.3 Safety Measures
To minimize the risks associated with barium compounds, it’s crucial to implement appropriate safety measures:
- Industrial Settings:
- Use proper ventilation to minimize dust and fume exposure.
- Wear appropriate personal protective equipment (PPE), such as respirators, gloves, and eye protection.
- Follow strict handling and disposal procedures.
- Medical Procedures:
- Administer barium sulfate suspensions under the supervision of qualified medical professionals.
- Ensure patients are properly hydrated to facilitate the excretion of barium sulfate after the procedure.
- Monitor patients for any adverse reactions.
- General Public:
- Avoid consuming food or water that may be contaminated with barium.
- Store barium-containing products securely, out of reach of children and pets.
- If you suspect barium poisoning, seek immediate medical attention.
5. Addressing Common Concerns about Barium
Here are some frequently asked questions about barium and its compounds:
| Question | Answer |
|---|---|
| Is barium harmful to humans? | Soluble barium compounds are toxic, but barium sulfate, used in medical imaging, is generally considered safe because it is insoluble and poorly absorbed by the body. |
| What are the symptoms of barium poisoning? | Symptoms may include muscle weakness, paralysis, irregular heartbeat, breathing difficulties, and gastrointestinal problems. |
| How is barium poisoning treated? | Treatment involves removing the barium from the body and providing supportive care. |
| Is barium exposure a concern for people living near oil and gas drilling sites? | While barium is present in drilling muds, the risk of exposure to the general public is generally low if proper safety measures are followed. |
| Are there environmental concerns associated with barium mining? | Barium mining can have environmental impacts, such as habitat destruction and water pollution. Responsible mining practices and environmental regulations can help mitigate these impacts. |
| Can barium be recycled? | Barium itself is not typically recycled, but barium-containing products may be recycled depending on the specific material. |
| What is the difference between barium and barium sulfate? | Barium is the element itself, while barium sulfate is a compound of barium, sulfur, and oxygen. Barium sulfate is insoluble and used in medical imaging, while soluble barium compounds are toxic. |
| Are there alternatives to barium sulfate for medical imaging? | In some cases, alternative contrast agents, such as iodine-based compounds, may be used. However, barium sulfate remains the preferred option for many GI imaging studies due to its effectiveness and relatively low cost. |
| What is the role of barium in fireworks? | Barium compounds, such as barium nitrate and barium chlorate, are used to produce green colors in fireworks. |
| Does barium have any nutritional value? | Barium has no known nutritional value and is not considered an essential element for human health. |
6. Interesting Facts About Barium
- The name “barium” comes from the Greek word “barys,” meaning “heavy,” referring to the high density of barium minerals.
- Barium was discovered in 1774 by Carl Wilhelm Scheele, but it wasn’t isolated until 1808 by Sir Humphry Davy.
- Barium is more abundant in the universe than elements like tin or molybdenum.
- The “Bologna stone,” a form of barium sulfide, was one of the first known phosphorescent materials.
- Barium is used in the manufacturing of spark plugs.
7. The Future of Barium Research and Applications
Research continues to explore new applications for barium and its compounds. Some areas of interest include:
- Advanced Materials: Developing new barium-containing materials with enhanced properties for various applications.
- Energy Storage: Investigating the potential of barium compounds in battery technology.
- Medical Imaging: Improving barium-based contrast agents for enhanced diagnostic capabilities.
- Environmental Remediation: Exploring the use of barium compounds for removing pollutants from water and soil.
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9. Conclusion: Barium’s Enduring Significance
Barium, with its unique properties and versatile applications, continues to play a vital role in various industries and scientific fields. From enhancing medical diagnostics to enabling efficient oil and gas extraction, barium compounds contribute significantly to our daily lives. By understanding the benefits, risks, and safety precautions associated with barium, we can harness its potential while minimizing any potential harm.
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10. Five Intentions for Searching “What is Barium”
Here are five common search intentions behind the query “What is barium?”:
- Definition and Basic Information: Users want a clear and concise definition of barium, including its atomic number, symbol, and position on the periodic table.
- Uses and Applications: Users are curious about the various uses of barium and its compounds in different industries, such as medicine, oil and gas, and manufacturing.
- Properties and Characteristics: Users seek information about the physical and chemical properties of barium, such as its appearance, melting point, boiling point, and reactivity.
- Safety and Hazards: Users are concerned about the potential risks and hazards associated with barium exposure and want to know about safety precautions.
- Medical Imaging: Users want to learn about the role of barium sulfate in medical imaging procedures, such as barium swallows and barium enemas.
11. Elaboration on Medical Uses of Barium Sulfate
Barium sulfate’s unique properties make it an ideal contrast agent for visualizing the gastrointestinal (GI) tract during X-ray and fluoroscopy examinations. Its high atomic number and insolubility in water contribute to its effectiveness and safety.
11.1 How Barium Sulfate Works
When a patient drinks or receives barium sulfate, it coats the lining of the esophagus, stomach, and intestines. Barium sulfate absorbs X-rays more strongly than surrounding tissues, creating a clear outline of the GI tract on the X-ray image. This allows doctors to identify abnormalities such as:
- Ulcers
- Tumors
- Polyps
- Inflammation
- Strictures (narrowing of the GI tract)
- Swallowing disorders
11.2 Types of Barium Sulfate Examinations
- Barium Swallow: Used to examine the esophagus and detect swallowing problems, esophageal reflux, and other abnormalities.
- Barium Meal: Used to examine the stomach and duodenum (the first part of the small intestine) to detect ulcers, tumors, and other conditions.
- Small Bowel Follow-Through: Used to examine the entire small intestine, often following a barium meal, to detect Crohn’s disease, tumors, and other abnormalities.
- Barium Enema: Used to examine the colon and rectum to detect polyps, tumors, diverticulitis, and other conditions.
11.3 Safety Considerations for Barium Sulfate
Barium sulfate is generally considered safe for most patients, but there are some potential risks and contraindications:
- Constipation: Barium sulfate can cause constipation, so patients are often advised to drink plenty of fluids after the examination to help eliminate the barium.
- Allergic Reactions: Allergic reactions to barium sulfate are rare but possible.
- Aspiration: In patients with swallowing difficulties, there is a risk of aspirating barium sulfate into the lungs, which can cause pneumonia.
- Perforation: In patients with a suspected GI perforation (a hole in the GI tract), barium sulfate should not be used, as it can leak into the abdominal cavity and cause peritonitis.
- Pregnancy: Barium sulfate is generally avoided during pregnancy due to the potential risk of radiation exposure to the fetus.
11.4 Advantages of Barium Sulfate
- Excellent Image Quality: Barium sulfate provides excellent visualization of the GI tract, allowing for accurate diagnosis of various conditions.
- Relatively Low Cost: Barium sulfate is a relatively inexpensive contrast agent compared to other options, such as iodine-based compounds.
- Generally Safe: Barium sulfate is generally considered safe for most patients, with a low risk of adverse reactions.
11.5 Alternatives to Barium Sulfate
In some cases, alternative contrast agents may be used instead of barium sulfate, such as:
- Iodine-Based Contrast Agents: These are used for CT scans and sometimes for X-rays, but they can cause allergic reactions and are not suitable for patients with kidney problems.
- Water-Soluble Contrast Agents: These are used when there is a suspected GI perforation, as they are less likely to cause peritonitis if they leak into the abdominal cavity.
12. Exploring Barium in Fireworks: The Green Connection
Barium compounds are essential for producing vibrant green colors in fireworks and pyrotechnics. This effect is due to the unique way barium atoms interact with heat and release energy as light.
12.1 How Barium Creates Green Light
When barium compounds are heated to high temperatures, such as during a firework explosion, the barium atoms become excited. Electrons within the atoms jump to higher energy levels. As these electrons return to their original energy levels, they release energy in the form of light.
The specific wavelengths of light emitted by barium atoms correspond to the color green. The most common barium compounds used in fireworks for green colors are:
- Barium Chlorate (Ba(ClO3)2)
- Barium Nitrate (Ba(NO3)2)
- Barium Chloride (BaCl2)
12.2 The Role of Barium Compounds
These barium compounds act as “colorants” in firework compositions. They are mixed with other ingredients, such as:
- Oxidizers: Provide oxygen to fuel the combustion process.
- Fuels: Provide the energy for the explosion and light emission.
- Binders: Hold the firework composition together.
- Stabilizers: Prevent the firework from detonating prematurely.
When the firework is ignited, the barium compound decomposes, releasing barium ions (Ba²⁺) that emit the characteristic green light.
12.3 Factors Affecting Green Color Intensity
The intensity and purity of the green color in fireworks depend on several factors:
- Barium Compound Concentration: Higher concentrations of barium compounds generally produce more intense green colors.
- Purity of Ingredients: Impurities in the firework composition can affect the color.
- Combustion Temperature: Higher combustion temperatures can enhance the green color.
- Other Additives: Certain additives, such as chlorine donors, can improve the color intensity and purity.
12.4 Safety Considerations for Fireworks
Fireworks contain explosive materials and should be handled with care. Always follow these safety precautions:
- Purchase fireworks from reputable sources.
- Use fireworks in a safe, open area, away from flammable materials.
- Never allow children to handle fireworks.
- Wear eye protection and other appropriate safety gear.
- Follow all local laws and regulations regarding fireworks.
12.5 Environmental Concerns
Perchlorate contamination is a growing concern in areas where fireworks are frequently used. Barium chlorate, a common ingredient in green fireworks, can contribute to perchlorate levels in the environment. Responsible firework practices and the development of alternative colorants can help mitigate these impacts.
13. Barium’s Role as a Getter in Vacuum Tubes
Barium’s unique properties make it an effective “getter” in vacuum tubes, which are used in various electronic devices. A getter is a material that is used to remove unwanted gases from a sealed system, such as a vacuum tube, to maintain a high vacuum.
13.1 What is a Vacuum Tube?
A vacuum tube is an electronic device that controls the flow of electrons in a vacuum. It typically consists of:
- A Cathode: Emits electrons when heated.
- An Anode (Plate): Collects the electrons.
- A Grid: Controls the flow of electrons between the cathode and anode.
Vacuum tubes were widely used in early electronic devices, such as radios, televisions, and amplifiers. While they have largely been replaced by transistors and integrated circuits, vacuum tubes are still used in some specialized applications, such as high-power amplifiers and certain audio equipment.
13.2 Why is a Vacuum Important?
A high vacuum is essential for the proper operation of vacuum tubes. The presence of gases inside the tube can interfere with the flow of electrons, leading to:
- Reduced performance
- Increased noise
- Shorter lifespan
13.3 How Barium Works as a Getter
Barium is an excellent getter material because it readily reacts with various gases, such as oxygen, nitrogen, and carbon dioxide. When barium is heated inside the vacuum tube, it forms a thin, reactive film on the inner walls of the tube. This film absorbs and chemically binds to any residual gases, effectively removing them from the vacuum.
The chemical reactions between barium and the gases form stable compounds, such as barium oxide (BaO), barium nitride (Ba3N2), and barium carbonate (BaCO3), which remain on the surface of the barium film.
13.4 Types of Barium Getters
Several types of barium getters are used in vacuum tubes:
- Flash Getters: These are small capsules containing barium that are heated to a high temperature, causing the barium to evaporate and deposit a thin film on the tube walls.
- Non-Evaporable Getters (NEGs): These are porous materials coated with barium that absorb gases without requiring evaporation.
- Barium Alloys: Barium is sometimes alloyed with other metals to improve its getter properties.
13.5 Advantages of Using Barium Getters
- High Efficiency: Barium getters are very effective at removing gases from vacuum tubes.
- Long Lifespan: Barium getters can maintain a high vacuum for extended periods.
- Relatively Low Cost: Barium is a relatively inexpensive material.
13.6 Modern Applications
While largely replaced, they are still critical in certain specialized high-power or high-fidelity applications.
14. Barium and Nuclear Fission: A Serendipitous Discovery
The discovery of barium’s presence after bombarding uranium with neutrons was a pivotal moment in science, leading to the understanding of nuclear fission.
14.1 The Experiment
In the late 1930s, scientists were bombarding uranium with neutrons to create heavier elements, known as transuranic elements. Otto Hahn and Fritz Strassmann, in their experiments, found unexpected results. After bombarding uranium with neutrons, they discovered barium, an element significantly lighter than uranium.
14.2 The Significance of Barium’s Presence
Lise Meitner and Otto Frisch, interpreting Hahn and Strassmann’s findings, realized that the uranium nucleus had split into two smaller nuclei, one of which was barium. This process, which they termed “nuclear fission,” released a tremendous amount of energy, confirming Einstein’s famous equation E=mc².
14.3 Nuclear Fission Explained
Nuclear fission occurs when the nucleus of a heavy atom, such as uranium or plutonium, splits into two or more smaller nuclei. This process releases a large amount of energy, as well as additional neutrons. These neutrons can then trigger further fission reactions, leading to a chain reaction.
14.4 Applications of Nuclear Fission
Nuclear fission has several important applications:
- Nuclear Power: Nuclear power plants use controlled nuclear fission to generate electricity.
- Nuclear Weapons: Nuclear fission is the basis for atomic bombs.
- Medical Isotopes: Nuclear fission is used to produce medical isotopes for diagnostic and therapeutic purposes.
- Research: Nuclear fission is used in scientific research to study the properties of atomic nuclei.
14.5 The Legacy of the Discovery
The discovery of nuclear fission revolutionized science and technology, leading to both tremendous benefits and significant challenges. It has provided us with a new source of energy but also raised concerns about nuclear weapons proliferation and the safe disposal of nuclear waste.
The serendipitous discovery of barium in the uranium bombardment experiments highlights the importance of curiosity-driven research and the potential for unexpected breakthroughs.
15. Delving into Barium Carbonate (BaCO3): Properties and Uses
Barium carbonate (BaCO3), also known as witherite, is an important barium compound with a variety of industrial applications.
15.1 Properties of Barium Carbonate
- Chemical Formula: BaCO3
- Molecular Weight: 197.34 g/mol
- Appearance: White powder
- Solubility: Insoluble in water, soluble in acids
- Crystal Structure: Orthorhombic
- Density: 4.43 g/cm³
- Decomposition Temperature: Decomposes at 1450 °C
15.2 Key Applications
- Glass Manufacturing: A significant portion of barium carbonate produced is used in the glass industry. It increases the refractive index of glass, making it sparkle, and enhances scratch resistance. It is also used in the production of specialty glasses, such as those used in television tubes and radiation shielding.
- Ceramics: Barium carbonate is used as a flux in the production of ceramics. It lowers the melting point of the ceramic mixture and helps to create a smooth, glossy finish.
- Brick Manufacturing: In the brick industry, barium carbonate is added to clay to precipitate soluble salts, such as calcium sulfate, which can cause efflorescence (a white, powdery deposit) on the surface of bricks.
- Rodenticide: Barium carbonate has been used as a rodenticide, but its toxicity makes it less common than other options.
- Chemical Synthesis: Barium carbonate is used as a starting material for the synthesis of other barium compounds.
15.3 Production Methods
Barium carbonate is typically produced by reacting barium sulfide (BaS) with sodium carbonate (Na2CO3) or carbon dioxide (CO2).
- Reaction with Sodium Carbonate: BaS + Na2CO3 → BaCO3 + Na2S
- Reaction with Carbon Dioxide: BaS + CO2 + H2O → BaCO3 + H2S
15.4 Safety Considerations
Barium carbonate is toxic if ingested or inhaled. Appropriate safety precautions should be taken when handling barium carbonate, including:
- Wearing personal protective equipment (PPE), such as gloves, eye protection, and a respirator.
- Working in a well-ventilated area.
- Avoiding contact with skin and eyes.
- Following proper disposal procedures.
15.5 Natural Occurrence
Barium carbonate occurs naturally as the mineral witherite, but it is relatively rare. Most barium carbonate used in industry is synthetically produced.
16. Barium Oxide (BaO): Production, Properties, and Uses
Barium oxide (BaO), also known as baryta, is another important barium compound with diverse applications.
16.1 Production of Barium Oxide
Barium oxide is typically produced by heating barium carbonate (BaCO3) to a high temperature:
BaCO3 → BaO + CO2
This process, known as calcination, releases carbon dioxide gas and leaves behind barium oxide.
16.2 Properties of Barium Oxide
- Chemical Formula: BaO
- Molecular Weight: 153.33 g/mol
- Appearance: White or yellowish-white powder
- Crystal Structure: Cubic
- Density: 5.72 g/cm³
- Melting Point: 1923 °C
- Boiling Point: Approximately 2000 °C
- Reactivity: Highly reactive with water and acids
16.3 Key Applications
- Preparation of Other Barium Compounds: Barium oxide is used as a starting material for the production of other barium compounds, such as barium hydroxide (Ba(OH)2) and barium peroxide (BaO2).
- Drying Agent: Barium oxide is a strong drying agent and is used to remove water from gases and solvents.
- High-Temperature Superconductors: Barium oxide is a component in some high-temperature superconductors, such as yttrium barium copper oxide (YBa2Cu3O7-x).
- Coatings for Cathodes: Barium oxide is used as a coating for cathodes in vacuum tubes, as it enhances their electron emission properties.
- Optical Glass: Barium oxide is added to optical glass to increase its refractive index and improve its clarity.
16.4 Reactions of Barium Oxide
- Reaction with Water: Barium oxide reacts vigorously with water to form barium hydroxide (Ba(OH)2), also known as baryta water:
BaO + H2O → Ba(OH)2
This reaction is exothermic, meaning it releases heat. Barium hydroxide is a strong base and is used in various chemical applications.
- Reaction with Acids: Barium oxide reacts with acids to form barium salts and water:
BaO + 2 HCl → BaCl2 + H2O
16.5 Safety Considerations
Barium oxide is corrosive and toxic. Appropriate safety precautions should be taken when handling barium oxide, including:
- Wearing personal protective equipment (PPE), such as gloves, eye protection, and a respirator.
- Working in a well-ventilated area.
- Avoiding contact with skin and eyes.
- Following proper disposal procedures.
16.6 Storage
Barium oxide should be stored in a tightly closed container in a dry, well-ventilated area, away from moisture and acids.
17. Barium Peroxide (BaO2): Properties, Production, and Applications
Barium peroxide (BaO2) is a compound of barium and oxygen that has been used in various applications, including the production of hydrogen peroxide and oxygen.
17.1 Production of Barium Peroxide
Barium peroxide can be produced by heating barium oxide (BaO) in air or oxygen at elevated temperatures:
2 BaO + O2 → 2 BaO2
The reaction is reversible, and the yield of barium peroxide is influenced by temperature and oxygen pressure.
17.2 Properties of Barium Peroxide
- Chemical Formula: BaO2
- Molecular Weight: 169.33 g/mol
- Appearance: Grayish-white or yellowish powder
- Crystal Structure: Tetragonal
- Density: 4.96 g/cm³
- Decomposition Temperature: Decomposes above 800 °C
17.3 Key Applications
- Production of Hydrogen Peroxide: Historically, barium peroxide was used to produce hydrogen peroxide (H2O2) through the following reaction with acid:
BaO2 + H2SO4 → H2O2 + BaSO4
The barium sulfate (BaSO4) precipitates out of the solution, leaving behind hydrogen peroxide.
- Oxygen Source: Barium peroxide can release oxygen when heated or reacted with water, making it useful as an oxygen source in certain applications.
- Bleaching Agent: Barium peroxide has been used as a bleaching agent for textiles and other materials.
- Igniter in Pyrotechnics: Barium peroxide can be used as an igniter in pyrotechnic compositions.
17.4 Reactions of Barium Peroxide
-
Reaction with Water: Barium peroxide reacts with water to form hydrogen peroxide and barium hydroxide:
BaO2 + 2 H2O → H2O2 + Ba(OH)2 -
Reaction with Acids: Barium peroxide reacts with acids to form hydrogen peroxide and barium salts:
BaO2 + 2 HCl → H2O2 + BaCl2
17.5 Safety Considerations
Barium peroxide is an oxidizing agent and can react violently with
