Statement I: Glass is not considered as a true compound. Statement I : Glass does not have a definite melting point.

examrobotsa's picture
Q: 34 (NDA-II/2013)
Statement I: Glass is not considered as a true compound.
Statement I : Glass does not have a definite melting point.

question_subject: 

Science

question_exam: 

NDA-II

stats: 

0,6,17,6,9,6,2

keywords: 

{'true compound': [0, 0, 0, 1], 'glass': [0, 0, 1, 4], 'definite melting point': [0, 0, 0, 2]}

Option 1 states that both statements are individually true and that Statement II is the correct explanation of Statement I. Let`s evaluate each statement separately.

Statement I: Glass is not considered as a true compound.

Glass is not considered a true compound because it does not have a fixed chemical composition. Unlike compounds, which have a specific arrangement of atoms, glass is an amorphous solid that lacks a repeating unit structure. It is made up of a mixture of different elements, such as silicon, sodium, and calcium, which are combined under specific conditions to form a non-crystalline substance.

Statement II: Glass does not have a definite melting point.

This statement is also true. Unlike crystalline solids that have a distinct melting point, glass is an amorphous solid that undergoes a gradual softening and becomes a liquid over a range of temperatures instead of a specific melting point. This behavior is called a glass transition.

Therefore, both statements are individually true. Additionally, Statement II is the correct explanation of Statement I because the lack of a definite melting point in glass is one of the reasons why it is not considered a true compound. Therefore, Option 1, which states that both statements are true and that Statement II explains Statement I, is the correct answer.