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Compound A formed in the following reaction reacts with B gives the product C. Find out A and B. CH_3-Cequiv CH + Na rightarrow A xrightarrowB CH_3-Cequiv C-CH_2-CH_2-CH_3 + NaBr

Solution & Explanation

### Core Logic Terminal alkynes possess acidic hydrogen. When treated with a strong base or active metal like Sodium (Na), they form sodium acetylide salts. CH_3-Cequiv C-H + Na rightarrow CH_3-Cequiv C^-Na^+ + frac12H_2 So, A is Sodium propynide (CH_3-Cequiv C^-Na^+). ### Step 1: Analyzing the second step The product is CH_3-Cequiv C-CH_2-CH_2-CH_3. This indicates an S_N2 substitution reaction between the acetylide ion (nucleophile) and an alkyl halide (electrophile). Since NaBr is a byproduct, B must be a propyl bromide. CH_3-Cequiv C^-Na^+ + CH_3-CH_2-CH_2-Br rightarrow CH_3-Cequiv C-CH_2-CH_2-CH_3 + NaBr ### Step 2: Conclusion A is CH_3-Cequiv C^-Na^+ and B is CH_3-CH_2-CH_2-Br (1-Bromopropane). ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 11 Chemistry: Hydrocarbons Class 12 Chemistry: Haloalkanes and Haloarenes

Reference Study Guides

Hydrocarbons

More Hydrocarbons Previous-Year Questions — Page 5

Q87 jee_main_2024_31_jan_morning Kolbe's Electrolysis
Number of alkanes obtained on electrolysis of a mixture of CH_3COONa and C_2H_5COONa is
Numerical Answer. Answer: 3 to 3

Solution

### Core Logic Kolbe's electrolytic method generates free radicals at the anode, which then combine to form alkanes. The given mixture yields two types of carboxylate radicals which decarboxylate to form alkyl radicals: CH_3COONa rightarrow dotCH_3 C_2H_5COONa rightarrow dotC_2H_5 These radicals can couple in three different ways: 1. Cross coupling: dotCH_3 + dotC_2H_5 rightarrow CH_3-CH_2-CH_3 (Propane) 2. Self-coupling 1: dotCH_3 + dotCH_3 rightarrow CH_3-CH_3 (Ethane) 3. Self-coupling 2: dotC_2H_5 + dotC_2H_5 rightarrow CH_3-CH_2-CH_2-CH_3 (Butane) Thus, a total of 3 different alkanes are formed. ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 11 Chemistry: Hydrocarbons

More Hydrocarbons Questions — jee_main_2024_30_jan_morning

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