Please mark below all of the statments that correctly describe the physical properties of glass.
a)Glasses do not have slip systems.
b)Glasses consist of both covalent and ionic bonding.
c)Glasses are brittle at room temperature.
d)Glasses are amorphous and have no long range symmetry.
e)The volume of a sample of glass depends on its cooling rate.
f)Glasses must consist of network formers and modifiers.
Glasses do not have slip systems
Glasses are brittle at room temperature Glasses are amorphous and have no long range symmetry
The volume of a sample of glass depends on its cooling rate
To determine which statements correctly describe the physical properties of glass, let's break down each statement individually:
a) Glasses do not have slip systems.
Explanation: This statement is correct. Unlike crystalline materials, such as metals, which have well-defined planes of atoms that can slide past each other (slip planes), glasses lack this kind of regular atomic arrangement and therefore do not possess slip systems.
b) Glasses consist of both covalent and ionic bonding.
Explanation: This statement is partially correct. Glasses primarily consist of covalent bonding, where atoms share electrons. However, not all glasses have ionic bonding. Some glasses may contain elements that create partially ionic bonds, but the majority of the bonding in glasses is covalent.
c) Glasses are brittle at room temperature.
Explanation: This statement is correct. Glass is known for its brittleness, meaning it tends to shatter or break into pieces when subjected to stress or strain. Unlike ductile materials, such as metals, that can deform without breaking, glass fractures easily.
d) Glasses are amorphous and have no long-range symmetry.
Explanation: This statement is correct. Glass is classified as an amorphous material, meaning it lacks long-range order or symmetry like crystalline materials. Instead, glass has a disordered atomic or molecular arrangement.
e) The volume of a sample of glass depends on its cooling rate.
Explanation: This statement is incorrect. The volume of glass does not depend on its cooling rate. Once glass has fully formed, it retains its shape and volume, regardless of the cooling rate. However, the cooling rate can affect the creation of defects or internal stresses in the glass, which can subsequently impact its mechanical properties.
f) Glasses must consist of network formers and modifiers.
Explanation: This statement is correct. To form a glass, it typically requires two main types of components: network formers and modifiers. Network formers, such as silicon dioxide (SiO2), create the backbone of the glass structure. Modifiers, such as sodium oxide (Na2O) or calcium oxide (CaO), are added to alter the properties of the glass, such as its melting temperature or chemical resistance.
Based on the explanations provided, the correct statements regarding the physical properties of glass are:
a) Glasses do not have slip systems.
c) Glasses are brittle at room temperature.
d) Glasses are amorphous and have no long-range symmetry.
f) Glasses must consist of network formers and modifiers.