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Which one of the following statements about glass is not correct?

Options

  1. AGlass is often said to be a supercooled liquid.
  2. BGlass has no definite melting point.
  3. CSoda glass is harder than pyrex glass.
  4. DBoron is present in pyrex glass.

Correct answer

C. Soda glass is harder than pyrex glass.

Step-by-step solution

In terms of hardness, Borosilicate glass is harder, stronger and more durable than Soda-lime glass. According to the Mohs scale of mineral hardness, diamond's rate is 10 , chalk is 1 , borosilicate comes in at 7.5 and the other types of glass at 6 .

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