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

Gujarat BoardEnglish MediumSTD 11 ScienceChemistryThe p-Block Elements5 Marks
Question
  1. Complete the following reactions:
  1. $8\text{BF}_3+6\text{LiH}\xrightarrow{\ \ \ \ \ \ \ \ \ \ }\ ........$
  2. $\text{H}_3\text{BO}_3\xrightarrow{\ \ \ \Delta\ \ \ }\ .........$
  3. $2\text{Al}+6\text{HCl}\xrightarrow{\ \ \ \ \ \ \ \ }\ .........$
  1. What are fullerenes? How are they prepared?
✓

Answer

  1.  
  1. $8\text{BF}_3+6\text{LiH}\xrightarrow{\ \ \ \ \ \ \ \ \ \ }\text{B}_2\text{H}_6+6\text{LiBF}_4$
  2. $\text{H}_3\text{BO}_3\xrightarrow{\ \ \ \Delta\ \ \ }\text{HBO}_2+\text{H}_2\text{O}$
  3. $2\text{Al}+6\text{HCl}\xrightarrow{\ \ \ \ \ \ \ \ }2\text{AlCl}_3+3\text{H}_2$
  1. Fullerenes are the purest form of carbon consisting of mainly $\mathrm{C}_{60}$ units. $\mathrm{C}_{60}$ unit has a shape of football and called Buckminster-fullerene. Fullerenes are prepared by heating graphite in an electric arc in the presence of inert gas such as helium or argon.

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