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-p-Block elements - I — Chemistry STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceChemistry-p-Block elements - I1 Mark
MCQ
Moissan boron is
  • A
    Amorphous boron of ultra purity
  • B
    Crystalline boron of ultra purity
  • ✓
    Amorphous boron of low purity
  • D
    Crystalline boron of low purity
✓

Answer

Correct option: C.
Amorphous boron of low purity
c
(c) Moissan boron is amorphous boron, obtained by reduction of ${B_2}{O_3}$ with $Na$ or $Mg$. It has $95-98\%$ boron and is black in colour.

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