5 Amorphous Solids

Which of the following is an example of an amorphous solid?

• Diamond

• Salt

• Glass

• Copper

What is the primary difference between the atomic-scale structure of a crystal and an amorphous solid?

• Crystals are always transparent, while amorphous solids are opaque.

• Crystals have random atomic arrangements, while amorphous solids have fixed positions.

• Crystals have higher densities than amorphous solids.

• Crystals have fixed lattice patterns, while amorphous solids lack long-range order.

In terms of response to shear stress, how do solids and liquids differ?

• Solids resist shear stress and maintain shape, while liquids flow easily.

• Solids flow easily and lack shape, while liquids resist shear stress.

• Both solids and liquids flow easily under shear stress.

• Neither solids nor liquids are affected by shear stress.

What happens to atomic mobility in solids as compared to liquids?

• Atoms in both solids and liquids move freely.

• Atoms in solids are not mobile and oscillate around a fixed point, while atoms in liquids are mobile and move freely.

• Atoms in both solids and liquids are fixed in place.

• Atoms in solids are mobile and move freely, while atoms in liquids are fixed.

What is the Glass Transition Temperature (Tg) indicative of?

• The temperature at which a material transitions from an amorphous solid to a liquid.

• The temperature at which a material transitions from a crystalline solid to an amorphous solid.

• The temperature at which a gas transitions to a liquid.

• The temperature at which a liquid transitions to a gas.

What is the primary function of the Pair Distribution Function in describing amorphous structure?

• It calculates the volume of the amorphous material.

• It measures the density of the amorphous material.

• It determines the color of the amorphous material.

• It provides information on the probability of finding a pair of atoms at a certain distance.

Which model is applicable to covalently bonded glasses like amorphous silicon?

• Crystal Model

• Random Close-Packing Model

• Continuous Random-Network Model

• Random-Coil Model

Which type of glass has properties like low thermal expansion, high softening temperatures, and excellent chemical resistance?

• Aluminosilicate Glasses

• Lead-Alkali-Silicate Glasses

• Soda-Lime-Silica Glasses

• Borosilicate Glasses

What is the significance of the Random-Coil Model in understanding the structure of amorphous materials?

• It describes the dense packing of atoms in metallic glasses.

• It explains the entangled polymer chains in organic polymeric glasses.

• It provides insights into the local structure of amorphous solids.

• It determines the refractive indices of amorphous materials.

What effect does the addition of soda (Na2O) have on silica glass?

• Increases the melting point and viscosity.

• Reduces the melting point and viscosity, but makes the glass more vulnerable to water.

• Enhances the durability by acting as a stabilizing oxide.

• Has no effect on the properties of silica glass.