KVPY Sample Paper KVPY Stream-SX Model Paper-22

  • question_answer
    \[C{{H}_{3}}C{{H}_{2}}OH\] can be converted into \[C{{H}_{3}}CHO\] by

    A) catalytic hydrogenation

    B) treatment with \[LiAl{{H}_{4}}\]

    C) treatment with pyridinium chlorochromate

    D) treatment with \[KMn{{O}_{4}}\]

    Correct Answer: C

    Solution :

    Ethanal \[\left( C{{H}_{3}}CHO \right)\] is an oxidized product of ethanol. Pyridinium chlorochromate \[\left( {{C}_{5}}{{H}_{5}}\overset{+}{\mathop{N}}\,\,HCl\,\overset{-}{\mathop{C}}\,\,r{{O}_{3}} \right)\] oxidises primary alcohols to aldehydes. Strong oxidising agents such as \[KMn{{O}_{4}}\] are used for getting-carboxylic acid from alcohols.
    The oxidation process can be stopped at the aldehyde stage, if \[Cr\left( VI \right)\] reagents such as Collin's reagent\[\left( Cr{{O}_{3}}.2{{C}_{5}}{{H}_{5}}N \right)\] Corey's reagent or pyridinium chlorochromate are used PCG and pyridinium dichromate\[\left[ \left( {{C}_{5}}{{H}_{5}}NH \right)_{2}^{2+}C{{r}_{2}}O_{7}^{2-} \right]\] in anhydrous medium are used as the oxidising agent. So, the correct option is [c]

You need to login to perform this action.
You will be redirected in 3 sec spinner