- 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) 1900
B) 1910
C) 1875
D) 1885
- 2. What is the atomic number of gallium?
A) 31
B) 32
C) 30
D) 33
- 3. Gallium is primarily used in which type of technology?
A) Semiconductors
B) Textiles
C) Pharmaceuticals
D) Automobiles
- 4. What form does gallium take at room temperature?
A) Liquid
B) Solid
C) Powder
D) Gas
- 5. Gallium arsenide (GaAs) is primarily used for?
A) High-frequency applications
B) Glassmaking
C) Cooking appliances
D) Fertilizers
- 6. Gallium is categorized under which group in the periodic table?
A) Group 12
B) Group 15
C) Group 14
D) Group 13
- 7. Gallium is primarily extracted from which type of ore?
A) Lead ore
B) Bauxite
C) Copper ore
D) Iron ore
- 8. What is a notable property of gallium?
A) Its low melting point
B) Its magnetic properties
C) Its radioactivity
D) Its high density
- 9. What color does gallium oxide appear?
A) White
B) Red
C) Green
D) Blue
- 10. Which country is the largest producer of gallium?
A) USA
B) Russia
C) Australia
D) China
- 11. What is the primary form in which gallium is used in electronics?
A) Gallium arsenide
B) Gallium chloride
C) Gallium sulfide
D) Gallium phosphide
- 12. Gallium is used in which process for creating semiconductors?
A) Thermal diffusion
B) Sputtering
C) Chemical vapor deposition
D) Molecular beam epitaxy
- 13. Gallium can affect the melting point of which metal when added?
A) Aluminum
B) Zinc
C) Copper
D) Iron
- 14. Gallium has a melting point just above which common temperature?
A) Room temperature
B) Freezing point of water
C) Boiling point of water
D) Absolute zero
- 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) Gold
B) Lead
C) Copper
D) Tungsten
- 17. Gallium's ability to form alloys is due to its?
A) High boiling point
B) Chemical reactivity
C) Low melting point
D) Radioactive nature
- 18. Where does gallium naturally occur?
A) In large mineral deposits
B) In seawater
C) In trace amounts in zinc and aluminum ores
D) In the atmosphere
- 19. Gallium can be used in which type of solar cell?
A) Perovskite cells
B) Crystalline silicon cells
C) Thin-film solar cells
D) Organic solar cells
- 20. What color is gallium in its pure form?
A) Black
B) Silvery-white
C) Blue
D) Gray
- 21. What is a significant compound of gallium used in LEDs?
A) Gallium nitride
B) Gallium oxide
C) Gallium sulfate
D) Gallium arsenide
- 22. Who discovered gallium?
A) Curie
B) Lecoq de Boisbaudran
C) Rutherford
D) Mendeleev
- 23. Which alloy contains gallium and is used for its low melting point?
A) Brass
B) Lead-Tin
C) Stainless Steel
D) Galinstan
- 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) 15.7 °C
B) 42.3 °C
C) 12.4 °C
D) 29.76 °C
- 26. Gallium can be solidified by?
A) Heating above its boiling point
B) Adding pressure
C) Cooling below its melting point
D) Mixing with water
|