Free Crystalline and Amorphous Solids MCQs with Answers

• A. Amorphous
• B. Crystalline
• C. Polycrystalline
• D. Quartz

Explanation: The materials in which the disordered structure of a liquid is frozen are typically referred to as amorphous solids. These materials do not have a long-range ordered structure like crystals, but instead, their atomic or molecular arrangements are disordered, similar to the structure of a liquid. One common example of such materials is glass.

• A. metallic solid.
• B. polymeric solid.
• C. crystalline solid.
• D. amorphous solid.

Explanation: Here's an explanation: * D) Amorphous solid: An amorphous solid is considered an intermediate structure between a solid and a liquid because it lacks the long-range, repeating, ordered atomic structure characteristic of a crystalline solid. Unlike crystalline solids, amorphous solids do not have a distinct melting point; instead, they gradually soften over a range of temperatures, behaving somewhat like very viscous liquids. This lack of a definitive structure and gradual transition behavior makes them intermediate. Glass, plastics, and gels are common examples of amorphous solids.

• A. glassy solids
• B. polymeric solids
• C. crystalline solids
• D. amorphous solids

Explanation: Nylon is classified as an amorphous solid because its molecular chains are arranged in a random or disordered manner, unlike the highly ordered structure of crystalline solids. This lack of long-range order gives amorphous solids unique properties. The other options are incorrect because nylon does not exhibit the characteristics of glassy, polymeric, or crystalline solids.

• A. I only.
• B. II only.
• C. I and III.
• D. II and III.

Explanation: The correct answer is I only. Amorphous solids are characterized by an irregular arrangement of molecules, which causes them to break into irregular fragments. In contrast, crystalline solids have a regular, repeating pattern of molecules, leading to well-defined fragments upon breaking. Polymers can have both regular and irregular structures, but the question specifically refers to the irregular arrangement leading to irregular fragments, which is characteristic of amorphous solids.

• A. Metamorphic
• B. Sedimentary
• C. Igneous
• D. Both Options A and B are correct

Explanation: Option A; Metamorphic rocks started out as some other type of rock, but have been substantially changed from their original igneous, sedimentary, or earlier metamorphic form. Option B: Common sedimentary rocks include sandstone, limestone, and shale. These rocks often start as sediments carried in rivers and deposited in lakes and oceans. When buried, the sediments lose water and become cemented to form rock.Option C: Igneous rocks (from the Latin word for fire) form when hot, molten rock crystallizes and solidifies. The melt originates deep within the Earth near active plate boundaries or hot spots, then rises toward the surface.

• A. Refraction
• B. Crystallization
• C. Volatilization
• D. Dispersion

Explanation: Ancient glass, an amorphous solid, undergoes alternate heating due to exposure to the sun during the day and cooling at night and is converted into partly crystalline form which results in the milky appearance. Refraction is the bending of light as it moves from a transparent substance into another. Volatilization is when a solid or liquid chemical substance is converted into vapours.

• A. Glass
• B. Diamond
• C. Silica
• D. Carbon

Explanation: Amorphous solids have the tendency to flow slowly. It does not form a crystalline solid structure as particles in solids do not move but here it moves. Hence it is called a supercooled liquid.Glass is amorphous solid

• A. Polarity
• B. Optical activity
• C. Anisotropy
• D. Cleavage plane

Explanation: .A is incorrect since polarity is a separation of electric charge leading to a molecule or its chemical groups having an electric dipole moment, with a negatively charged end and a positively charged end. Polarity has no link to the refractive index or electrical conductivity in one direction. B is incorrect since optical activity is the ability of a substance to rotate the plane of polarization of a beam of light that is passed through it. Optical activity has no link to the refractive index or electrical conductivity in one direction. C is correct since the physical properties that depend upon the direction are called anisotropic properties and the phenomenon is referred to as anisotropy. The physical properties of crystalline solids like refractive index, coefficient of thermal expansion, and electrical and thermal conductivities are sometimes anisotropic for some crystals. The variation in these properties with direction is because the orderly arrangement of the particles in crystalline solids is different in different directions. For example, the electrical conductivity of graphite is greater in one direction than in another. D is incorrect since the plane surfaces formed by the breaking of a crystal are known as crystal cleavage planes. The angle between the adjacent cleavages of a crystal of a substance are the same but are different in the crystals of different substances. In other words, these angles are characteristics of crystalline solids. Cleavage itself is an anisotropic property but not what the question is asking for.

• A. critical temperature
• B. absolute temperature
• C. Curie Temperature
• D. normal temperature

Explanation: Ferromagnetic MATERIALS can be permanently magnetized. Curie Temperature: The temperature at which the ferromagnetic element starts to lose its magnetism and becomes paramagnetic. Understanding the above-stated facts, option 'C' is the correct answer.

• A. Amorphous substances have a sharp melting point
• B. Amorphous substances do not have a fixed melting point
• C. Amorphous substances have proper geometrical shapes
• D. The particles in amorphous substances are arranged in an orderly manner

Explanation: Amorphous solids, unlike crystalline solids, do not have a fixed melting point. This is because they lack the ordered structure that characterizes crystalline materials. Instead, they soften gradually over a range of temperatures. For example, glass softens before melting completely. Amorphous solids have a disordered atomic or molecular structure, which results in their unique properties such as isotropic behavior and lack of sharp melting points. Option B correctly identifies this characteristic, whereas the other options incorrectly attribute properties of crystalline solids to amorphous ones.