Atomic mass:54.938 u
Manganese: Element Overview
Basic Information
- Symbol: Mn
- Atomic Number: 25
- Atomic Weight: 54.938044 u
- Element Category: Transition metal
- Group: 7
- Period: 4
Physical Properties
- Phase at Room Temperature: Solid
- Melting Point: 1246 °C (2275 °F)
- Boiling Point: 2061 °C (3742 °F)
- Density: 7.21 g/cm³ at 20 °C
- Color: Silvery-gray
- Crystal Structure: Body-centered cubic (bcc)
Chemical Properties
- Electronegativity: 1.55 (Pauling scale)
- Ionization Energies:
- First: 717.3 kJ/mol
- Second: 1509 kJ/mol
- Third: 3248 kJ/mol
- Oxidation States: +7, +6, +4, +3, +2 (most common are +2, +4, and +7)
- Reactivity: Manganese is reactive with oxygen, forming manganese dioxide (MnO₂). It also reacts with acids to form manganese salts.
Isotopes
- Stable Isotopes: Manganese has one stable isotope: Mn-55.
- Radioisotopes: Several radioisotopes, including Mn-53, which is used in geology for isotope dating.
Occurrence and Production
- Natural Abundance: Manganese is the 12th most abundant element in the Earth’s crust.
- Sources: Found in minerals such as pyrolusite (MnO₂), rhodochrosite (MnCO₃), and manganite (MnO(OH)).
- Production: Produced by reducing manganese dioxide with carbon in a blast furnace or electric furnace.
Uses and Applications
- Steel Production: Essential in steelmaking as a deoxidizer and alloying element to improve strength, toughness, and wear resistance.
- Batteries: Used in dry cell batteries and alkaline batteries as manganese dioxide.
- Alloys: Used in aluminum alloys to improve corrosion resistance and mechanical properties.
- Chemicals: Used in the production of potassium permanganate (KMnO₄), a strong oxidizing agent used in disinfectants and water treatment.
- Pigments: Manganese compounds are used to produce pigments for paints, ceramics, and glass.
- Agriculture: Used as a micronutrient in fertilizers to promote plant growth.
Safety and Precautions
- Reactivity: Manganese is relatively reactive, especially in powdered form, and can react with water and air.
- Handling: Manganese and its compounds should be handled with care to avoid inhalation and ingestion.
- Toxicity: Prolonged exposure to manganese dust or fumes can cause manganese poisoning, affecting the nervous system. It is important to use appropriate protective equipment.
Biological Role
- Essential Element: Manganese is essential for all living organisms.
- Enzyme Function: Plays a crucial role in the functioning of several enzymes involved in metabolism, bone formation, and antioxidant defense.
- Health: Required in trace amounts for human health, particularly for bone development and wound healing.
Historical Background
- Discovery: Discovered by Johann Gottlieb Gahn in 1774.
- Naming: The name “manganese” is derived from the Latin word “magnes,” meaning magnet, due to its magnetic properties.
Interesting Facts
- Manganese Nodules: Found on the ocean floor, these nodules are rich in manganese and other valuable metals.
- Colorful Compounds: Manganese compounds exhibit a variety of colors, including pink (Mn²⁺), green (Mn⁶⁺), and purple (Mn⁷⁺).
- Manganese Bronze: An alloy of copper and manganese known for its high strength and resistance to corrosion.
Summary
Manganese is a versatile transition metal known for its crucial role in steel production, batteries, and various industrial applications. Discovered in the 18th century, manganese is essential for living organisms and plays a vital role in enzymatic functions. It is produced primarily from manganese dioxide and is used in a wide range of products, from steel alloys to fertilizers. While beneficial in trace amounts, manganese must be handled with care due to its potential toxicity.
Questions and Answers about Manganese:
Q: What is the chemical symbol for Manganese?
- A: Mn
Q: What is the atomic number of Manganese?
- A: 25
Q: What type of element is Manganese?
- A: Transition metal
Q: What is the atomic weight of Manganese?
- A: 54.938044 u
Q: What group is Manganese in?
- A: Group 7
Q: What period is Manganese in?
- A: Period 4
Q: What is the phase of Manganese at room temperature?
- A: Solid
Q: What is the melting point of Manganese?
- A: 1246 °C (2275 °F)
Q: What is the boiling point of Manganese?
- A: 2061 °C (3742 °F)
Q: What is the density of Manganese at 20 °C?
- A: 7.21 g/cm³
Q: What is the color of Manganese metal?
- A: Silvery-gray
Q: What is the crystal structure of Manganese?
- A: Body-centered cubic (bcc)
Q: What is the electronegativity of Manganese?
- A: 1.55 (Pauling scale)
Q: What is the first ionization energy of Manganese?
- A: 717.3 kJ/mol
Q: How many stable isotopes does Manganese have?
- A: One (Mn-55)
Q: What is the most common isotope of Manganese?
- A: Mn-55
Q: How is Manganese commercially produced?
- A: By reducing manganese dioxide with carbon in a blast furnace or electric furnace
Q: What is the natural abundance of Manganese in the Earth’s crust?
- A: 12th most abundant element
Q: What common minerals contain Manganese?
- A: Pyrolusite (MnO₂), rhodochrosite (MnCO₃), manganite (MnO(OH))
Q: What industry uses Manganese extensively for steel production?
- A: Steel and construction industry
Q: What is one use of Manganese in the battery industry?
- A: Used in dry cell and alkaline batteries as manganese dioxide
Q: What role does Manganese play in the production of aluminum alloys?
- A: Improves corrosion resistance and mechanical properties
Q: Why is Manganese used in agriculture?
- A: Used as a micronutrient in fertilizers to promote plant growth
Q: What is the biological role of Manganese in the body?
- A: Plays a crucial role in the functioning of several enzymes
Q: Who discovered Manganese?
- A: Johann Gottlieb Gahn
Q: In what year was Manganese discovered?
- A: 1774
Q: What is the origin of the name “Manganese”?
- A: Derived from the Latin word “magnes,” meaning magnet
Q: What property makes Manganese reactive with oxygen?
- A: Forms manganese dioxide (MnO₂)
Q: What health hazard is associated with prolonged exposure to Manganese dust or fumes?
- A: Can cause manganese poisoning, affecting the nervous system
Q: How should Manganese and its compounds be handled?
- A: With care to avoid inhalation and ingestion, using appropriate protective equipment
Q: What is the second ionization energy of Manganese?
- A: 1509 kJ/mol
Q: What is the third ionization energy of Manganese?
- A: 3248 kJ/mol
Q: Is Manganese essential for plant health?
- A: Yes, it is essential for plant growth
Q: What is the significance of Manganese in enzyme function?
- A: Crucial for the functioning of several enzymes involved in metabolism and bone formation
Q: What is the role of Manganese in the production of potassium permanganate?
- A: Used to produce potassium permanganate (KMnO₄), a strong oxidizing agent
Q: How does Manganese benefit the steel industry?
- A: Improves strength, toughness, and wear resistance of steel
Q: What is Manganese’s role in the production of pigments?
- A: Used to produce pigments for paints, ceramics, and glass
Q: What is the use of Manganese in refractories?
- A: Used in the manufacture of refractory materials that withstand high temperatures
Q: How does Manganese contribute to the production of dry cell batteries?
- A: Used as manganese dioxide in the batteries
Q: What color are Manganese compounds typically?
- A: They can exhibit a variety of colors, including pink, green, and purple
