Preparation of Bakelite proceeds via reactions:

Options

A. (a) Electrophilic subtitution and dehydration
B. (b) Nucleophilic additon and dehydration
C. (c) Electrophilic addition and dehydration
D. (d) Condensation and elimination

Answer

To solve the question regarding the preparation of Bakelite, we need to analyze the reactions involved in its synthesis. Bakelite is a type of phenolic resin formed from the reaction of phenol and formaldehyde. Here’s a step-by-step breakdown of the process:

### Step 1: Understanding the Reactants
Bakelite is synthesized from phenol (C6H5OH) and formaldehyde (HCHO).

### Step 2: Electrophilic Substitution Reaction
In the first step, phenol reacts with formaldehyde. The hydroxyl group (-OH) on the phenol ring is an activating group that directs electrophilic substitution at the ortho and para positions of the aromatic ring.

- **Reaction**:
\[ \text{C}_6\text{H}_5\text{OH} + \text{HCHO} \rightarrow \text{C}_6\text{H}_4(\text{CH}_2\text{OH}) + \text{H}_2\text{O} \]
This results in the formation of ortho- and para-hydroxymethylphenol.

### Step 3: Further Electrophilic Substitution
The hydroxymethylphenol can further react with more formaldehyde. This can happen at the ortho position again, leading to additional substitutions.

### Step 4: Condensation Reaction
As more of these hydroxymethylphenol units form, they begin to condense. This condensation reaction involves the elimination of water (dehydration), leading to the formation of a larger polymer structure.

- **Reaction**:
\[ n(\text{C}_6\text{H}_4(\text{CH}_2\text{OH})) \rightarrow \text{Bakelite} + (n-1)\text{H}_2\text{O} \]
This step is crucial as it leads to the formation of Bakelite, which is a thermosetting polymer.

### Conclusion
From the above steps, we can conclude that the preparation of Bakelite involves:
1. Electrophilic substitution (reaction of phenol with formaldehyde).
2. Condensation (dehydration leading to polymer formation).

Thus, the correct answer to the question is **electrophilic substitution and dehydration**.

### Final Answer
The preparation of Bakelite proceeds via **electrophilic substitution and dehydration**.

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