Question

Which one of the following is a thermosetting plastic?

• A. Polyvinyl chloride (PVC)
• B. Polyvinyl acetate (PVA)
• C. Bakelite
• D. None of these

Hint:

Bakelite is a thermosetting plastic, while PVC and PVA are thermoplastics that can be re-shaped.

Answer 1

The Correct Option is C

Step 1: Define thermosetting plastics.
Thermosetting plastics are plastics that harden when heated and cannot be re-melted or re-shaped after the first heating.
Step 2: Analyze the options.
- Bakelite (Option C) is a thermosetting plastic that is formed by the polymerization of phenol and formaldehyde. It hardens permanently after heating and is used for electrical insulators. - PVC (Option A) and PVA (Option B) are thermoplastics, which can be re-melted and re-shaped. - None of these (Option D) is incorrect.
Step 3: Apply to the options.
The correct answer is (C) Bakelite.
Final Answer: \[ \boxed{\text{Bakelite}} \]