AP EAMCET201824 Apr 2018Evening ShiftChemistryHydrocarbonsActual
Assertion (A) : Reaction of 1-butene with HBr gives 1-bromobutane as major product. Reason ( R ) : Addition of HBr to unsymmetrical alkenes proceeds according to Markovnikov's rule The correct answer is
Options
- A(A) and (R) are correct, (R) is the correct explanation of (A)
- B(A) and (R) are correct but (R) is not the correct explanation of (A)
- C(A) is correct but (R) is not correct
- D(A) is not correct but (R) is correct
Correct answer
D. (A) is not correct but (R) is correct
Step-by-step solution
- Assertion (A): "Reaction of 1-butene with HBr gives 1-bromobutane as a major product." This is incorrect. According to Markovnikov's rule, the hydrogen atom of HBr adds to the carbon atom of the double bond that already has more hydrogen atoms. Thus, in the reaction of 1butene ( ( CH ₃- CH ₂- CH = CH ₂ )) with HBr, the hydrogen adds to ( CH ₂ ) and the bromine adds to the second carbon atom ( (C H )) to give 2-bromobutane as the major product. - Reason (R): "Addition of HBr to unsymmetrical alkenes proceeds accor