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Directions : (11 - 15)

Case III : Read the passage given below and answer the following questions from 11 to 15.

Dehydration of alcohols can lead to the formation of either alkenes or ethers. This dehydration can be carried out either with protonic acids such as cone. \[{{H}_{2}}S{{O}_{4}}\], \[{{H}_{3}}P{{O}_{4}}\] or catalysts such as anhydrous \[ZnC{{l}_{2}}\]or\[A{{l}_{2}}{{O}_{3}}\]. When primary alcohols are heated with cone. \[{{H}_{2}}S{{O}_{4}}\] at 433-443 K, they undergo intramolecular dehydration to form alkenes. Secondary and tertiary alcohols undergo dehydration under milder conditions.

The ease of dehydration of alcohols follows the order :\[3{}^\circ \text{ }>\text{ }2{}^\circ \text{ }>\text{ }1{}^\circ \].

The dehydration of alcohols always occurs in accordance with the Saytzeff's rule. Primary alcohols when heated with protic acid at 413 K, gives dialkyl ether.

\[C{{H}_{3}}C{{H}_{2}}OH\xrightarrow[433-443\,K]{conc.\,{{H}_{2}}S{{O}_{4}}}C{{H}_{2}}=C{{H}_{2}}+{{H}_{2}}O\]

\[2C{{H}_{3}}C{{H}_{2}}OH\xrightarrow[413\,K]{conc.\,{{H}_{2}}S{{O}_{4}}}\]

\[C{{H}_{3}}C{{H}_{2}}-O-C{{H}_{2}}C{{H}_{3}}+{{H}_{2}}O\]

Which one of the following alcohols undergoes acid-catalysed dehydration to alkenes most readily?

A) \[{{\left( C{{H}_{3}} \right)}_{2}}CHC{{H}_{2}}OH\]

B) \[{{\left( C{{H}_{3}} \right)}_{3}}COH\]

C) \[C{{H}_{3}}CHOHC{{H}_{3}}\]

D) \[C{{H}_{3}}C{{H}_{2}}C{{H}_{2}}OH\]