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Question
Which reagent will you use for the following reaction?
\[\ce{CH3CH2CH2CH3 -> CH3CH2CH2CH2Cl + CH3CH2CHClCH3}\]
Options
Cl2/UV light
\[\ce{NaCl + H2CO4}\]
Cl2 gas in dark
Cl2 gas in the presence of iron in dark
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Solution
Cl2/UV light
Explanation:
Free radical chlorination or bromination of alkanes gives a complex mixture of isomeric mono- and polyhaloalkanes, which is difficult to separate as pure compounds. In this case, a mixture of the two isomeric forms of butane is obtained by the use of Cl2/UV light as per the reaction below -
\[\ce{CH3CH2CH2CH3 ->[Cl2/UV light][or heat] CH3CH2CH2CH2Cl + CH3CH2CHClCH3}\]
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|
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\[\begin{array}{cc}\ce{CH3CHCH2CH2Br}\\|\phantom{.........}\\\ce{CH3}\phantom{......}\end{array}\] or \[\begin{array}{cc}\ce{CH3CH2CHCH2Br}\\\phantom{}|\\\phantom{...}\ce{CH3}\end{array}\]
