- 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) 1885
B) 1875
C) 1910
D) 1900
- 2. What is the atomic number of gallium?
A) 31
B) 33
C) 30
D) 32
- 3. Gallium is primarily used in which type of technology?
A) Automobiles
B) Textiles
C) Pharmaceuticals
D) Semiconductors
- 4. What form does gallium take at room temperature?
A) Powder
B) Liquid
C) Gas
D) Solid
- 5. Gallium arsenide (GaAs) is primarily used for?
A) Glassmaking
B) Fertilizers
C) Cooking appliances
D) High-frequency applications
- 6. Gallium is categorized under which group in the periodic table?
A) Group 15
B) Group 14
C) Group 12
D) Group 13
- 7. Gallium is primarily extracted from which type of ore?
A) Bauxite
B) Lead ore
C) Copper ore
D) Iron ore
- 8. What is a notable property of gallium?
A) Its radioactivity
B) Its magnetic properties
C) Its low melting point
D) Its high density
- 9. What color does gallium oxide appear?
A) Green
B) White
C) Red
D) Blue
- 10. Which country is the largest producer of gallium?
A) Australia
B) Russia
C) China
D) USA
- 11. Gallium's ability to form alloys is due to its?
A) High boiling point
B) Radioactive nature
C) Chemical reactivity
D) Low melting point
- 12. Gallium can be solidified by?
A) Mixing with water
B) Heating above its boiling point
C) Cooling below its melting point
D) Adding pressure
- 13. Gallium has a melting point just above which common temperature?
A) Freezing point of water
B) Boiling point of water
C) Room temperature
D) Absolute zero
- 14. What is a significant compound of gallium used in LEDs?
A) Gallium arsenide
B) Gallium sulfate
C) Gallium nitride
D) Gallium oxide
- 15. Gallium can be used in which type of solar cell?
A) Organic solar cells
B) Perovskite cells
C) Crystalline silicon cells
D) Thin-film solar cells
- 16. Which of the following is a medical application of gallium?
A) Surgical tools
B) Pain relievers
C) Gallium scans in imaging
D) Vaccines
- 17. Which isotope of gallium is most stable?
A) Gallium-71
B) Gallium-68
C) Gallium-69
D) Gallium-70
- 18. What is the primary form in which gallium is used in electronics?
A) Gallium phosphide
B) Gallium sulfide
C) Gallium chloride
D) Gallium arsenide
- 19. Gallium can affect the melting point of which metal when added?
A) Aluminum
B) Zinc
C) Iron
D) Copper
- 20. What color is gallium in its pure form?
A) Silvery-white
B) Black
C) Gray
D) Blue
- 21. Gallium is used in which process for creating semiconductors?
A) Chemical vapor deposition
B) Thermal diffusion
C) Molecular beam epitaxy
D) Sputtering
- 22. Where does gallium naturally occur?
A) In seawater
B) In the atmosphere
C) In trace amounts in zinc and aluminum ores
D) In large mineral deposits
- 23. Who discovered gallium?
A) Curie
B) Lecoq de Boisbaudran
C) Rutherford
D) Mendeleev
- 24. What is the melting point of gallium?
A) 12.4 °C
B) 29.76 °C
C) 15.7 °C
D) 42.3 °C
- 25. Which alloy contains gallium and is used for its low melting point?
A) Stainless Steel
B) Brass
C) Galinstan
D) Lead-Tin
- 26. Gallium's thermal conductivity is higher than which material?
A) Lead
B) Tungsten
C) Copper
D) Gold
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