Cartain materials such as turpentine oil, unsaturated organic compound, phosophorus, metals such as `Zn`, and `Pb`, etc., can absorb `O_(2)` from air in the presence of `H_(2)O`, which is converted to absorb `O_(2)` from air in the presence of `H_(2)O`, which is converted to `H_(2)O_(2)`. This is called autoxidation. Intermolecular redox reactions are those in which one molecule is oxidised and the other is reduced. Intramolecular redox reactions are those in which oen atom of a molecule is oxidised and the other atom is reduced.
Which of the following reactions is//are intramolecular redox reactions (s) ?

Options

A. `2Mn_(2)O_(7)rarr4MnO_(2)+3O_(2)`
B. `K_(3)[Fe(CN)_(6)]+30H_(2)OrarrFe^(3+)+6CO_(2)+6NO_(3)^(ө)+60H^(o+)+60e^(-)`
C. `2HgOrarr2Hg+O_(2)`
D. `PhCHOoverset(NaOH)rarrPhCH_(2)OH+PhCOONa`

Answer

A, C

Explanation

Hence, it is an intramolecular redox reaction.
b. It is an intramolecular redox reaction.
c. It is an intramolecular redox reaction.
`{:(2e^(-)+,Hg^(2+),rarr,Hg,("Reduction")),(,2O_(2)^(2-),rarr,O_(2)+4e^(-),("Oxidation")):}`
d. It is a disproportionation reaction.