Q7 / 50 · Manipal (MET) 2024 · Chemistry

$F_2$ is formed by reacting $\mathrm{K}_2 \mathrm{MnF}_6$ with

  • Correct answer
    A
    $\mathrm{SbF}_5$
  • B
    $\mathrm{MnF}_3$
  • C
    $\mathrm{KSbF}_6$
  • D
    $\mathrm{MnF}_4$

Solution

$\mathrm{K}_2 \mathrm{MnF}_6$ react with $\mathrm{SbF}_5$ to form $\mathrm{F}_2$. In this reaction stronger Lewis acid $\mathrm{SbF}_5$ displace the weaker one $\left(\mathrm{MnF}_4\right)$ from its salt. $\mathrm{MnF}_4$ being unstable, readily decompose to give $\mathrm{MnF}_3$ and fluorine. The complete reaction is as follows, $\mathrm{K}_2 \mathrm{MnF}_6+2 \mathrm{SbF}_5 \longrightarrow 2 \mathrm{KSbF}_6+\mathrm{MnF}_4$ (unstable) $2 \mathrm{MnF}_4 \longrightarrow 2 \mathrm{MnF}_3+\mathrm{F}_2$ Overall reaction, $2 \mathrm{~K}_2 \mathrm{MnF}_6+4 \mathrm{SbF}_5 \longrightarrow 4 \mathrm{KSbF}_6+2 \mathrm{MnF}_3+\mathrm{F}_2$

Hence, the correct answer is option: 'A'.

Relevant Questions