Medium MCQ +4 / -1 PYQ · JEE Mains 2023

Reaction of BeO with ammonia and hydrogen fluoride gives A which on thermal decomposition gives $\mathrm{BeF_2}$ and $\mathrm{NH_4F}$. What is 'A'?

  1. A $\mathrm{(NH_4)Be_2F_5}$
  2. B $\mathrm{(NH_4)_2BeF_4}$ Correct answer
  3. C $\mathrm{(NH_4)BeF_3}$
  4. D $\mathrm{H_3NBeF_3}$

Solution

$$ \mathrm{BeO}+\mathrm{NH}_{3}+\mathrm{HF} \longrightarrow\left(\mathrm{NH}_{4}\right)_{2} \underset{(\mathrm{A})}{\mathrm{BeF}_{4}} \stackrel{\Delta}{\longrightarrow} \mathrm{BeF}_{2}+\mathrm{NH}_{4} \mathrm{~F} $$ <br/><br/> Compound $\mathrm{A}$ is $\left(\mathrm{NH}_{4}\right)_{2} \mathrm{BeF}_{4}$

About this question

Subject: Chemistry · Chapter: s-Block Elements · Topic: Alkali Metals

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