Question

which of the following processes do not represent oxidation

Answer 1

aldehyde changed to alcohol processes do not represent oxidation

Answer 2

Answer:

The conversion of aldehyde to alcohol does not represent oxidation.

Therefore, the option (C) is correct.

Explanation:

During the reaction, addition of oxygen or removal of hydrogen or loss of electrons is called oxidation. In the oxidation process, the oxidation number of substance increases. The substance which undergoes a oxidation can acts as a reducing agent in a redox reaction.

• Conversion of alcohol into acid is oxidation process. For this process oxidizing agent such as PCC, Jone's reagent or KMnO₄ are used.

        The conversion as : R-CH₂OH  +  [O] $\longrightarrow$    R-COOH

• Conversion of cuprous ion into cupric is a oxidation process.  Cupric ion formed by the loss of one electron from cuprous ion. There is increase in oxidation number of copper by one.

         Cu⁺   $\longrightarrow$   Cu²⁺    +   e⁻

• Conversion of aldehyde into alcohol is not a oxidation process. There is addition of hydrogen, so it is reduction. Reducing agent such as LiAlH₄, NaBH₄, Ni etc. are used.

         RCHO  + [H]   $\longrightarrow$  R-CH₂OH  

• Conversion of solid sodium into sodium ion is a oxidation process.  Sodium ion formed by the loss of one electron from sodium metal. There is increase in oxidation number of sodium by one.

         Na (s)  $\longrightarrow$   Na⁺    +   e⁻