Organic Reaction Mechanism: Major Product Determination

This question involves identifying the major product of a reaction where an alkene undergoes electrophilic addition. Based on the structure shown in the first image (C=C with CH₃ and H substituents), this appears to be propene reacting with HBr.

Step-by-Step Explanation:

Step 1: Identify the reaction type - This is electrophilic addition of HBr to an unsymmetrical alkene (propene).

Step 2: Apply Markovnikov's Rule - The hydrogen atom adds to the carbon with more hydrogen atoms, while the bromine adds to the carbon with more alkyl substituents.

Step 3: For propene $CH 3 -CH=CH 2$ :

H⁺ adds to CH₂ (less substituted carbon)
Br^- adds to CH- (more substituted carbon)

Step 4: The major product is 2-bromopropane: $CH 3 -CHBr-CH 3$

Final Answer: The second option (image showing CH₃-CHBr-CH₃) is the correct major product.

Related Topics:

Markovnikov's Rule
Electrophilic Addition Reactions
Carbocation Stability
Alkene Reactivity

Important Formulae and Theory:

Markovnikov's Rule: In the addition of HX to an unsymmetrical alkene, the hydrogen atom attaches to the carbon with the greater number of hydrogen atoms.

Carbocation Stability Order: Tertiary > Secondary > Primary > Methyl

General Reaction: Alkene + HX → Alkyl halide (following Markovnikov orientation)