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Question: The final product obtained by the reaction between alcohol and phosphorus pentachloride is:...

The final product obtained by the reaction between alcohol and phosphorus pentachloride is:

Explanation

Solution

We know that alcohols are organic compounds that contain hydroxyl groups. We can write the general representation of alcohol is ROHR - OH. We have to know that when alcohols react with halogen such as chlorine, bromine, iodine etc, the hydroxyl group gets replaced by halogen atoms.

Complete answer:
We have to know when alcohol is reacted with halogen like chlorine, and bromine. The hydroxyl group is replaced by halogen atoms. We can write the general equation as,
ROH+HXRX+H2OROH + HX\xrightarrow[{}]{}RX + {H_2}O
So, when alcohols react with phosphorus (V) chloride (or) phosphorus pentachloride, the product formed would be chloro alkanes along with gaseous hydrogen chloride. The reaction of phosphorus pentachloride with alcohol is a good test to show the presence of hydroxyl groups. The general reaction of phosphorus pentachloride and alcohol would be given as,
ROH+PCl5RCl+POCl3+HClROH + PC{l_5}\xrightarrow[{}]{}RCl + POC{l_3} + HCl
We have to know that when phosphorus pentachloride is reacted with alcohol, clouds of hydrogen chloride are formed. POCl3POC{l_3} is also formed as a side product in the reaction.
For example: Butanol reacts with phosphorus pentachloride to form butyl chloride, POCl3POC{l_3} and hydrogen chloride. The chemical reaction is written as,
CH3CH2CH2OH+PCl5CH3CH2CH2Cl+POCl3+HClC{H_3}C{H_2}C{H_2}OH + PC{l_5}\xrightarrow[{}]{}C{H_3}C{H_2}C{H_2}Cl + POC{l_3} + HCl
So, we have to know that the final product obtained is chloroalkane when phosphorus pentachloride and alcohol are reacted to one other.

Note:
We have to know that phosphorus pentachloride could also be used as chlorinating agents. It could easily be contaminated with HClHCl and appears sensitive to water and is colorless solid. The geometry of phosphorus pentachloride is trigonal bipyramidal and is otherwise known as pentachloro phosphorane. When alcohol reacts with phosphorus trichloride in liquid state, other groups which react with PCl5PC{l_5} gets eliminated first and chloroalkane are formed.