Americium (Am)

General Information

• Symbol: Am
• Atomic Number: 95
• Atomic Weight: 243 u
• Element Category: Actinide
• Group: N/A (Actinides series)
• Period: 7
• Block: f-block

Physical Properties

• Appearance: Silvery-white metallic, tarnishes slowly in air
• Density: 12 g/cm³
• Melting Point: 1176 °C (2149 °F)
• Boiling Point: 2607 °C (4725 °F)
• Phase at STP: Solid
• Electron Configuration: [Rn] 5f⁷ 7s²
• Oxidation States: +3 (most common), +2, +4, +5, +6

Chemical Properties

• Reactivity: Americium is reactive, forming a variety of compounds. It reacts with oxygen, water, and acids.
• Compounds: Forms compounds such as americium dioxide (AmO₂), americium(III) chloride (AmCl₃), and americium(III) nitrate (Am(NO₃)₃).

Uses and Applications

• Smoke Detectors: Americium-241 is commonly used in smoke detectors as an ionization source.
• Neutron Sources: Used as a neutron source in industrial radiography and research.
• Nuclear Batteries: Americium-241 can be used in radioisotope thermoelectric generators (RTGs) for space missions and remote applications.

Occurrence and Extraction

• Natural Occurrence: Americium does not occur naturally and is a synthetic element.
• Production: Produced in nuclear reactors from neutron bombardment of plutonium or uranium.

Isotopes

• Stable Isotopes: Americium has no stable isotopes.
• Radioactive Isotopes: The most common isotopes are Americium-241 (half-life of 432.2 years) and Americium-243 (half-life of 7,370 years).

Safety and Handling

• Hazards: Americium is highly radioactive and poses significant health risks. It can cause radiation poisoning and cancer if inhaled or ingested.
• Precautions: Handle with extreme care, using appropriate protective equipment and working in controlled environments. Proper disposal of radioactive materials is crucial.

History

• Discovery: Discovered by Glenn T. Seaborg, Albert Ghiorso, and their team in 1944.
• Name Origin: Named after the Americas, as it follows the element Curium, which was named after Marie and Pierre Curie.

Additional Facts

• Crystal Structure: Double hexagonal close-packed (dhcp)
• Magnetic Properties: Paramagnetic
• Thermal Conductivity: 10 W/m·K
• Electrical Resistivity: 69 µΩ·cm at 0°C

Summary

Americium is a synthetic element used primarily in smoke detectors, neutron sources, and nuclear batteries. Discovered in 1944, it is produced in nuclear reactors and requires careful handling due to its high radioactivity.

40 Question and Answer Pairs About Americium

1. What is the atomic number of Americium?

   • 95

2. What is the symbol for Americium?

   • Am

3. What is the atomic weight of Americium?

   • 243 u

4. In which group of the periodic table is Americium found?

   • Actinides series (no specific group)

5. What period is Americium in?

   • Period 7

6. What block does Americium belong to?

   • f-block

7. What is the density of Americium?

   • 12 g/cm³

8. What is the melting point of Americium?

   • 1176 °C (2149 °F)

9. What is the boiling point of Americium?

   • 2607 °C (4725 °F)

10. What is the electron configuration of Americium?

    • [Rn] 5f⁷ 7s²

11. What are the common oxidation states of Americium?

    • +3 (most common), +2, +4, +5, +6

12. What is the appearance of Americium?

    • Silvery-white metallic

13. Is Americium reactive with air?

    • Yes, it tarnishes slowly.

14. Name a compound of Americium.

    • Americium dioxide (AmO₂)

15. What is a common use of Americium-241 in households?

    • Used in smoke detectors.

16. How is Americium used in industrial applications?

    • Used as a neutron source in industrial radiography.

17. What role does Americium play in space missions?

    • Used in RTGs for power generation.

18. How is Americium typically produced?

    • By neutron bombardment of plutonium or uranium in nuclear reactors.

19. What is the most common isotope of Americium for smoke detectors?

    • Americium-241

20. How is Americium extracted?

    • Produced synthetically in nuclear reactors.

21. What safety hazard is associated with Americium dust?

    • It is highly radioactive and poses significant health risks.

22. Who discovered Americium?

    • Glenn T. Seaborg, Albert Ghiorso, and their team

23. Where does the name Americium come from?

    • Named after the Americas.

24. What is the crystal structure of Americium at room temperature?

    • Double hexagonal close-packed (dhcp)

25. Is Americium paramagnetic or diamagnetic at room temperature?

    • Paramagnetic

26. What is the thermal conductivity of Americium?

    • 10 W/m·K

27. What is the electrical resistivity of Americium at 0°C?

    • 69 µΩ·cm

28. What is the primary oxidation state of Americium in its compounds?

    • +3

29. Is Americium found as a free element in nature?

    • No, it is a synthetic element.

30. What is the common name of Americium(III) chloride?

    • AmCl₃

31. What is a major application of Americium in household safety?

    • Smoke detectors.

32. How does Americium benefit industrial radiography?

    • Used as a neutron source.

33. What is the melting point of Americium in Kelvin?

    • 1449 K

34. What group does Americium belong to in the periodic table?

    • Actinides series

35. What is the natural abundance of Americium-241?

    • It is produced synthetically and is not found naturally.

36. Can Americium be used in high-temperature applications?

    • Yes, particularly in RTGs for space missions.

37. What is the key property that makes Americium valuable in smoke detectors?

    • Its ability to ionize air particles.

38. How is Americium used in the chemical industry?

    • Mainly in research and specialized applications.

39. What precautions should be taken when handling Americium?

    • Use appropriate protective equipment to avoid inhalation or ingestion.

40. What are the health risks associated with Americium?

    • It can cause radiation poisoning and cancer if inhaled or ingested.