Question
Prove that acidified potassium dichromate is a powerful oxidising agent.

Answer

$K _2 Cr _2 O _7$ act as power oxidising agent in acidic medium. In the presence of $H ^{+}$ions, the oxidation state of $Cr$ froms $Cr ^{6+}$ is changed to $Cr ^{3+}$
$
Cr _2 O _7^{2-}+14 H ^{+}+6^{-} \rightarrow 2 Cr ^{3+}+6 Fe ^{3+}+7 H _2 O
$
Example:
Acidified $K _2 Cr _2 O _7$ oxidises Ferrous salts to Ferric salts.
$
Cr _2 O _7^{2-}+6 Fe ^{2+}+14 H ^{+} \rightarrow 2 Cr ^{3+}+6 Fe ^{3+}+7 H _2 O \text {. }
$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free