 - 1. Gallium, a post-transition metal with the atomic number 31, was first discovered in 1875 by the French chemist Paul-Émile Lecoq de Boisbaudran, who identified it through its spectral lines and named it after the Latin name for France, 'Gallia'. This remarkable element has sparked significant interest in modern technology due to its unique properties, such as a low melting point of approximately 29.76 °C, which allows it to exist as a liquid just above room temperature. Consequently, gallium is utilized in various applications, including the production of high-performance semiconductors, as it forms gallium arsenide (GaAs), a crucial material for high-speed electronics, solar cells, and optoelectronic devices like LEDs and laser diodes. Furthermore, gallium nitride (GaN), another compound derived from gallium, has emerged as a revolutionary material for efficient power transistors, enabling improved energy efficiency in power supplies and radio-frequency applications. Its ability to withstand high temperatures and voltages makes gallium a key player in the advancement of modern telecommunications and power electronics. Additionally, gallium has been explored for use in medicine, particularly in treatment modalities involving gallium nitrate for its anticancer properties. The ongoing research into gallium's potential in quantum computing and its integration in new materials highlights its indispensable role in shaping the technology of the future, marking it as an essential element in both present and emergent technologies.
In what year was gallium discovered?
A) 1910
B) 1875
C) 1900
D) 1885
- 2. What is the atomic number of gallium?
A) 31
B) 32
C) 33
D) 30
- 3. Gallium is primarily used in which type of technology?
A) Automobiles
B) Semiconductors
C) Pharmaceuticals
D) Textiles
- 4. What form does gallium take at room temperature?
A) Solid
B) Powder
C) Gas
D) Liquid
- 5. Gallium arsenide (GaAs) is primarily used for?
A) Fertilizers
B) Glassmaking
C) Cooking appliances
D) High-frequency applications
- 6. Gallium is categorized under which group in the periodic table?
A) Group 12
B) Group 13
C) Group 15
D) Group 14
- 7. Gallium is primarily extracted from which type of ore?
A) Bauxite
B) Iron ore
C) Lead ore
D) Copper ore
- 8. What is a notable property of gallium?
A) Its magnetic properties
B) Its low melting point
C) Its radioactivity
D) Its high density
- 9. What color does gallium oxide appear?
A) Green
B) Blue
C) White
D) Red
- 10. Which country is the largest producer of gallium?
A) Australia
B) USA
C) China
D) Russia
- 11. What is the primary form in which gallium is used in electronics?
A) Gallium chloride
B) Gallium sulfide
C) Gallium arsenide
D) Gallium phosphide
- 12. Gallium is used in which process for creating semiconductors?
A) Thermal diffusion
B) Molecular beam epitaxy
C) Chemical vapor deposition
D) Sputtering
- 13. Gallium can affect the melting point of which metal when added?
A) Copper
B) Zinc
C) Iron
D) Aluminum
- 14. Gallium has a melting point just above which common temperature?
A) Freezing point of water
B) Absolute zero
C) Boiling point of water
D) Room temperature
- 15. Which of the following is a medical application of gallium?
A) Vaccines
B) Pain relievers
C) Surgical tools
D) Gallium scans in imaging
- 16. Gallium's thermal conductivity is higher than which material?
A) Lead
B) Tungsten
C) Copper
D) Gold
- 17. Gallium's ability to form alloys is due to its?
A) Low melting point
B) Radioactive nature
C) Chemical reactivity
D) High boiling point
- 18. Where does gallium naturally occur?
A) In large mineral deposits
B) In trace amounts in zinc and aluminum ores
C) In the atmosphere
D) In seawater
- 19. Gallium can be used in which type of solar cell?
A) Perovskite cells
B) Crystalline silicon cells
C) Organic solar cells
D) Thin-film solar cells
- 20. What color is gallium in its pure form?
A) Black
B) Silvery-white
C) Gray
D) Blue
- 21. What is a significant compound of gallium used in LEDs?
A) Gallium arsenide
B) Gallium oxide
C) Gallium nitride
D) Gallium sulfate
- 22. Who discovered gallium?
A) Curie
B) Mendeleev
C) Rutherford
D) Lecoq de Boisbaudran
- 23. Which alloy contains gallium and is used for its low melting point?
A) Galinstan
B) Lead-Tin
C) Brass
D) Stainless Steel
- 24. Which isotope of gallium is most stable?
A) Gallium-70
B) Gallium-71
C) Gallium-69
D) Gallium-68
- 25. What is the melting point of gallium?
A) 42.3 °C
B) 12.4 °C
C) 29.76 °C
D) 15.7 °C
- 26. Gallium can be solidified by?
A) Cooling below its melting point
B) Mixing with water
C) Adding pressure
D) Heating above its boiling point
|