Unit 4: Liquids and Solids

41. In which type of solid do particles form a lattice structure, and each ion is surrounded by oppositely charged ions?

a) Metallic solid
b) Molecular solid
c) Ionic solid
d) Covalent solid
Answer: c) Ionic solid

42. The temperature at which the vapor pressure of a liquid equals the external pressure is called:

a) Freezing point
b) Boiling point
c) Melting point
d) Condensation point
Answer: b) Boiling point

43. The ability of a liquid to form a meniscus in a container is an example of:

a) Viscosity
b) Surface tension
c) Capillarity
d) Density
Answer: c) Capillarity

44. In which type of solid are particles arranged in a random manner with no long-range order?

a) Crystalline solid
b) Amorphous solid
c) Molecular solid
d) Ionic solid
Answer: b) Amorphous solid

45. The energy required to change a substance from a liquid to a gas at constant temperature is called:

a) Heat of fusion
b) Heat of vaporization
c) Heat of sublimation
d) Heat of condensation
Answer: b) Heat of vaporization

46. Which of the following describes a solid where the atoms are held together by a network of covalent bonds throughout the entire solid?

a) Molecular solid
b) Covalent network solid
c) Metallic solid
d) Ionic solid
Answer: b) Covalent network solid

47. The phenomenon where liquid rises in a narrow tube due to adhesive and cohesive forces is called:

a) Surface tension
b) Capillarity
c) Viscosity
d) Evaporation
Answer: b) Capillarity

48. The energy required to convert one mole of a solid into a liquid at its melting point is called:

a) Heat of vaporization
b) Heat of fusion
c) Heat of sublimation
d) Heat of condensation
Answer: b) Heat of fusion

49. Which type of solid is typically hard, brittle, and has a high melting point?

a) Molecular solid
b) Ionic solid
c) Metallic solid
d) Amorphous solid
Answer: b) Ionic solid

50. The phase transition from a solid directly to a gas is known as:

a) Sublimation
b) Condensation
c) Melting
d) Freezing
Answer: a) Sublimation