MCQ
Silicon dissolves in excess of $HF$ due to formation of
  • A
    $SiF_4$
  • B
    $SiH_4$
  • C
    $H_2SiF_6$
  • D
    $H_2SiF_4$

Answer

$HF$ is a very strong acid and can also react with silicon and corrode its lattice
$\mathrm{Si}+4 \mathrm{HF} \rightarrow \mathrm{SiF}_{4}+4 \mathrm{H}^{+}$
$\downarrow \mathrm{HF}$
$\mathrm{H}_{2} \mathrm{SiF}_{6}$

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