Chemistry Multiple Choice Questions on “Classification of Crystalline Solids”.
1. Which of the following consists of either atoms or molecules formed by non polar covalent bonds?
a) Non polar molecular solid
b) Metallic solid
c) Polar molecular solid
d) Ionic solid
Answer: a
Clarification: Non polar molecular solids consists of either of the atoms or molecules formed by non polar covalent bonds. Metallic solids and ionic solids consist of free mobile electrons and ions respectively. Whereas polar molecular solids are formed by polar covalent bonds.
2. Polar molecular solids are _________
a) bad conductors of electricity
b) good conductors of electricity
c) solid at room temperature
d) brittle
Answer: a
Clarification: In polar molecular solids, the molecules are formed by covalent bonds and held together by strong dipole-dipole interaction. Therefore, polar molecular solids are non-conductors of electricity.
3. The molecules in polar molecular solid are held together by __________
a) dipole-dipole interaction
b) london forces
c) ionic bond
d) metallic bond
Answer: a
Clarification: The force responsible for holding together the molecules of polar molecular solids is dipole-dipole force of attraction. Polar molecular solids are non-conductors of electricity.
4. Which of the following tend to be volatile liquids or soft solids at room temperature and pressure?
a) Non polar molecular solids
b) Metallic solids
c) Polar molecular solids
d) Hydrogen bonded molecular solids
Answer: d
Clarification: In hydrogen bonded molecular solid, the intermolecular forces are strong hydrogen bonds. Hence, it tends to be volatile liquids or soft solids at room temperature and pressure.
5. Which type of solids are formed by three-dimensional arrangement of cations and anions bound by strong electrostatic force?
a) Polar molecular solids
b) Ionic solids
c) Covalent solids
d) Metallic solids
View Answer
Answer: b
Clarification: Ionic solids are made up of three dimensional arrangement of cations and anions bound by strong electrostatic force.
6. Which of the following is non-conductor of electricity at solid state but can conduct electricity in the molten state or when dissolved in water?
a) Non polar molecular solids
b) Metallic solids
c) Ionic solids
d) Hydrogen bonded molecular solids
Answer: c
Clarification: Ionic Solids, when dissolved in water, tend to separate cations and the anions which allows the solution to conduct electricity. Also, they have high melting and boiling points.
7. Which of the following is an orderly collection of positive ions surrounded and held together by a sea of electrons?
a) Gas
b) Non-metal
c) Metal
d) Metalloids
Answer: c
Clarification: Metal is said to be an orderly collection of positive ions surrounded and held together by a sea of delocalized electrons. These delocalized electrons are mobile and are responsible for the conduction of electricity.
8. Which of the following are responsible for high electrical and thermal conductivity of a metal?
a) Ions
b) Covalent bonds
c) Free H+ ions
d) Free and mobile electrons
Answer: d
Clarification: Each atom of a metal gives one or more electrons towards the sea of mobile electrons it is surrounded by which ultimately contributes to the electrical and thermal conductivity of the metal.
9. Which of the following is not a characteristic of metals?
a) Lustre
b) Ductile
c) Malleable
d) Brittle
Answer: d
Clarification: Metals are lustrous, ductile and malleable. They cannot be brittle. Non-metals tend to be brittle in their solid state.
10. Which type of crystalline solid is also called as giant molecules?
a) Ionic solids
b) Covalent solids
c) Polar molecular solids
d) Metallic solids
Answer: b
Clarification: Covalent solids consists of a long chain of covalent bonds between the adjacent molecules throughout the crystal. Hence, they are called giant molecules. They are hard and brittle in nature.