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99 Percentile Qs Bank for JEE MainChemistryp Block Elements (Group 13 & 14)

The building units of various crystalline forms of boron are:

Options

  1. AB 12 icosahedral units
  2. BB 4 tetrahedral units
  3. CB 6 octahedral units
  4. DB 8 cubical units

Correct answer

A. B 12 icosahedral units

Step-by-step solution

Crystalline boron consists of B 12 icosahedral units having 12 corners and twenty faces. Each corner is represented by a thickened circle as shown in the figure.

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