Explanation:
Ethanol can be oxidized to ethanal or acetaldehyde which is further oxidized to acid that is acetic acid.
[tex]CH_3CH_2OH[/tex]→ [tex]CH_3CHO[/tex] [oxidation by loss of hydrogen]
Acetaldehyde can also be reduced back to ethanol again by adding hydrogen to it by using a reducing agent that is sodium tetrahydro borate, NaBH4.
[tex]CH_3CHO[/tex] → [tex]CH_3CH_2COOH[/tex] [reduction by the gain of electrons]
Here, the oxidizing agent used is[tex]Cr_3O[/tex] in the presence of acetone.