Question

Which of the following glasses is the most heat resistant?

• A. Bottle glass
• B. Flint glass
• C. Water glass
• D. Pyrex glass

Answer 1

Answer: (D)

Pyrex glass

Answer 2

Boron sesquioxide $B _{2} O _{3}$ is used in making borosilicates, heat resistant pyrex glass. Pyrex glass contains $14 \% B _{2} O _{3}$.