Zirconium (Zr)

General Information

• Symbol: Zr
• Atomic Number: 40
• Atomic Weight: 91.224 u
• Element Category: Transition metal
• Group: 4
• Period: 5
• Block: d-block

Physical Properties

• Appearance: Silvery-white, lustrous metallic
• Density: 6.52 g/cm³
• Melting Point: 1855 °C (3371 °F)
• Boiling Point: 4409 °C (7968 °F)
• Phase at STP: Solid
• Electron Configuration: [Kr] 4d² 5s²
• Oxidation States: +4 (most common), +2, +3

Chemical Properties

• Reactivity: Resistant to corrosion; reacts with oxygen and nitrogen at high temperatures.
• Compounds: Forms compounds such as zirconium dioxide (ZrO₂), zirconium tetrachloride (ZrCl₄), and zirconium carbide (ZrC).

Uses and Applications

• Nuclear Industry: Used as cladding for nuclear reactor fuels due to its low absorption of neutrons.
• Materials Science: Zirconium dioxide (zirconia) is used in ceramic materials, dental implants, and laboratory crucibles.
• Chemical Industry: Used in the production of corrosion-resistant alloys and in chemical piping.
• Jewelry: Used in cubic zirconia (ZrO₂), a synthetic gemstone that resembles diamonds.

Occurrence and Extraction

• Natural Occurrence: Found primarily in the mineral zircon (ZrSiO₄) and baddeleyite (ZrO₂).
• Extraction: Extracted from zircon through processes such as the Kroll process, involving reduction with magnesium.

Isotopes

• Stable Isotopes: Zirconium-90, Zirconium-91, Zirconium-92, Zirconium-94
• Radioactive Isotope: Zirconium-93

Safety and Handling

• Hazards: Generally considered to be of low toxicity, but zirconium powder can be flammable.
• Precautions: Handle zirconium powder with care to avoid fire hazards; standard laboratory safety procedures apply.

History

• Discovery: Discovered by Martin Heinrich Klaproth in 1789.
• Name Origin: Named after the mineral zircon.

Additional Facts

• Crystal Structure: Hexagonal close-packed (hcp) at room temperature; body-centered cubic (bcc) at higher temperatures.
• Magnetic Properties: Paramagnetic
• Thermal Conductivity: Moderate, about 22.6 W/m·K
• Electrical Resistivity: About 421 nΩ·m at room temperature

Summary

Zirconium is a transition metal known for its corrosion resistance, making it valuable in nuclear reactors, materials science, and the chemical industry. It forms various compounds, including zirconium dioxide used in ceramics and jewelry. Its stable isotopes make it useful in multiple applications, while its extraction primarily comes from the mineral zircon through reduction processes.

1. What is the atomic number of Zirconium?

   • 40

2. What is the symbol for Zirconium?

   • Zr

3. What is the atomic weight of Zirconium?

   • 91.224 u

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

   • Group 4

5. What period is Zirconium in?

   • Period 5

6. What block does Zirconium belong to?

   • d-block

7. What is the melting point of Zirconium?

   • 1855 °C (3371 °F)

8. What is the boiling point of Zirconium?

   • 4409 °C (7968 °F)

9. What is the density of Zirconium?

   • 6.52 g/cm³

10. What is the electron configuration of Zirconium?

    • [Kr] 4d² 5s²

11. What are the common oxidation states of Zirconium?

    • +4, +2, +3

12. What is the appearance of Zirconium?

    • Silvery-white, lustrous metallic

13. Is Zirconium reactive with oxygen?

    • Yes, at high temperatures

14. Name a compound of Zirconium.

    • Zirconium dioxide (ZrO₂)

15. What is a common use of Zirconium in the nuclear industry?

    • Cladding for nuclear reactor fuels

16. How is Zirconium used in materials science?

    • In ceramic materials and dental implants

17. What role does Zirconium play in the chemical industry?

    • Used in corrosion-resistant alloys and chemical piping

18. How is Zirconium used in jewelry?

    • In cubic zirconia (ZrO₂), a synthetic gemstone

19. Name a mineral that contains Zirconium.

    • Zircon (ZrSiO₄)

20. How is Zirconium extracted from minerals?

    • Through the Kroll process

21. What is the most stable isotope of Zirconium?

    • Zirconium-90

22. Name a radioactive isotope of Zirconium.

    • Zirconium-93

23. What safety hazard is associated with Zirconium powder?

    • It can be flammable

24. Who discovered Zirconium?

    • Martin Heinrich Klaproth

25. Where does the name Zirconium come from?

    • Named after the mineral zircon

26. What is the crystal structure of Zirconium at room temperature?

    • Hexagonal close-packed (hcp)

27. Is Zirconium paramagnetic or diamagnetic?

    • Paramagnetic

28. What is the thermal conductivity of Zirconium?

    • About 22.6 W/m·K

29. What is the electrical resistivity of Zirconium at room temperature?

    • About 421 nΩ·m

30. What is the primary oxidation state of Zirconium?

    • +4

31. Is Zirconium found as a free element in nature?

    • No, it is found in minerals

32. What process is used to extract Zirconium from zircon?

    • The Kroll process

33. What type of crystal structure does Zirconium have at higher temperatures?

    • Body-centered cubic (bcc)

34. What is a major application of Zirconium dioxide (ZrO₂)?

    • Used in ceramics and dental implants

35. How does Zirconium improve alloys?

    • It increases corrosion resistance

36. What is the boiling point of Zirconium in Kelvin?

    • 4712 K

37. What group does Zirconium belong to in the periodic table?

    • Transition metals

38. What is the natural abundance of Zirconium-90?

    • About 51.45%

39. Can Zirconium be used in high-temperature applications?

    • Yes, due to its high melting point

40. What is the key property that makes Zirconium valuable in the nuclear industry?

    • Its low absorption of neutrons and corrosion resistance.