Match List I with List II
| List I | List II |
| A. Wurtz reaction | i. \(Ni\) |
| B. Sabatier-Sender's reaction | ii. \(Zn\) |
| C. Frankland reaction | iii. \(CaO + NaOH\) |
| D. Decarboxylation | iv. \(Na\) |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is option 2. A-iv, B-i, C-ii, D-iii.
Let us delve into the details of each reaction and the associated metals:
A. Wurtz Reaction: iv. \(Na\)
The Wurtz reaction involves the coupling of two alkyl halides in the presence of sodium metal to form a new carbon-carbon bond. The general reaction is as follows:
\(2R-X + 2Na \longrightarrow R-R + 2NaX \)
Where \( R \) represents an alkyl group and \( X \) is a halogen. Sodium (Na) acts as the reducing agent in this reaction, promoting the formation of the carbon-carbon bond. This reaction is particularly useful for synthesizing symmetrical alkanes.
B. Sabatier-Senderens Reaction: i. \(Ni\)
The Sabatier-Senderens reaction refers to the hydrogenation of alkenes or alkynes to alkanes using a nickel catalyst. The reaction is typically carried out under conditions of elevated temperature and pressure. The general reaction is:
\( R-CH=CH-R' + H_2 \overset{Ni}{\longrightarrow} R-CH_2-CH_2-R'\)
Nickel (Ni) serves as the catalyst that facilitates the addition of hydrogen (H\(_2\)) to the carbon-carbon double or triple bonds, converting them into single bonds and thus forming alkanes.
C. Frankland Reaction: ii. \(Zn\)
The Frankland reaction involves the formation of organozinc compounds by the reaction of zinc with alkyl halides. The general reaction is:
\(2R-X + 2Zn \longrightarrow R_2Zn + ZnX_2 \)
Where \( R \) is an alkyl group and \( X \) is a halogen. Zinc (Zn) is crucial for the formation of the organozinc compound, which can be used in various organic synthesis reactions.
D. Decarboxylation: iii. \(CaO + NaOH\)
Decarboxylation is the process of removing a carboxyl group from a carboxylic acid, releasing carbon dioxide (CO\(_2\)). The reaction is often carried out using soda lime, a mixture of calcium oxide (CaO) and sodium hydroxide (NaOH). The general reaction is:
\(R-COOH \overset{CaO + NaOH}{\longrightarrow} R-H + CO_2\)
Soda lime facilitates the decarboxylation, making it a practical method for converting carboxylic acids into hydrocarbons.
Thus, the correct matching is: 2. A-iv, B-i, C-ii, D-iii.