What is the atomic number of boron element?

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RPF SI (2018) Official Paper (Held On: 24 Dec, 2018 Shift 1)
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  1. 5
  2. 8
  3. 6
  4. 7

Answer (Detailed Solution Below)

Option 1 : 5
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Detailed Solution

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The correct answer is 5

Key Points

  • The atomic number of the boron element is 5.
  • The atomic number is defined as the number of protons found in the nucleus of an atom.
  • Boron is a chemical element with the symbol B and is classified as a metalloid.
  • It is used in various applications, including borosilicate glass and as a semiconductor in electronics.

Additional Information

  • Boron was discovered by Sir Humphry Davy, Joseph Louis Gay-Lussac, and Louis Jacques Thénard in 1808.
  • It has an atomic mass of approximately 10.81 u (atomic mass units).
  • Boron compounds such as borax and boric acid have been used historically in glass and ceramics.
  • The element is essential for plant growth and is used in small quantities in agriculture.
  • Boron has two naturally occurring stable isotopes, B-10 and B-11, with B-11 being the more abundant.
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