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The p-Block Elements — Chemistry STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceChemistryThe p-Block Elements1 Mark
MCQ
Borax contains the tetranuclear units. Thus, its formula can be written as:
  • A
    $[\text{Na}_2\text{B}_4\text{O}_5(\text{OH})_4].8\text{H}_2\text{O}$
  • ✓
    $\text{Na}_2[\text{B}_4\text{O}_5(\text{OH)}_4].8\text{H}_2\text{O}$
  • C
    $[\text{Na}_2\text{B}_4\text{O}_5(\text{OH})_6].6\text{H}_2\text{O}$
  • D
    None of the above.
✓

Answer

Correct option: B.
$\text{Na}_2[\text{B}_4\text{O}_5(\text{OH)}_4].8\text{H}_2\text{O}$

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