Which one of the following statements is not correct? Vulcanisation of rubber makes it A. Soft and flexible B. Strong and hard C. Chemical resistant D. Withstand higher temperatures

The correct answer is: A. Soft and flexible.

Vulcanization is a chemical process that makes rubber more durable and resistant to heat, cold, and chemicals. It is achieved by adding sulfur to rubber and then heating it. The sulfur cross-links the rubber molecules, making them stronger and more resistant to damage.

The other options are all correct. Vulcanization makes rubber stronger and harder, which makes it more resistant to wear and tear. It also makes rubber more chemical resistant, which means it can be used in a wider range of applications. Finally, vulcanization makes rubber withstand higher temperatures, which means it can be used in more extreme environments.

Here is a more detailed explanation of each option:

• Option A: Soft and flexible. Vulcanization does not make rubber softer or more flexible. In fact, it makes rubber stronger and harder, which makes it less flexible.
• Option B: Strong and hard. Vulcanization does make rubber stronger and harder. This is because the sulfur cross-links the rubber molecules, making them more resistant to damage.
• Option C: Chemical resistant. Vulcanization does make rubber more chemical resistant. This is because the sulfur cross-links make the rubber molecules less reactive to chemicals.
• Option D: Withstand higher temperatures. Vulcanization does make rubber withstand higher temperatures. This is because the sulfur cross-links make the rubber molecules less likely to break down at high temperatures.