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

Gujarat BoardEnglish MediumSTD 11 ScienceChemistryThe p-Block Elements3 Marks
Question
Explain the following reactions:
  1. Silicon dioxide is treated with hydrogen fluoride.
  2. Carbon is heated with ZnO.
  3. Hydrated Alumina is treated with aqueous NaOH solution.
✓

Answer

  1. $\text{SiO}_2+6\text{HF}\xrightarrow{\ \ \ \ \ }\text{H}_2\text{SiF}_6+2\text{H}_2\text{O}\\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ ^\text{Fluosilicic}\\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ ^\text{acid}$
  2. $\text{ZnO}+\text{C}\xrightarrow{\ \ \ \ \ \ \ }\text{Zn}+\text{CO}$
  3. $\text{Al}_2\text{O}_3.2\text{H}_2\text{O}+2\text{NaOH}+\text{H}_2\text{O}\xrightarrow{\ \ \ \ \ \ \ }\\2\text{Na[Al(OH})_4]$

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