Practice important
Molecular Polarization
MCQ questions and answers.
Page 1
of
1
|
10
MCQ Questions
1. What is molecular polarization in an insulating material?
A.
The separation or alignment of positive and negative charges within molecules
B.
The flow of free electrons through the material
C.
The breaking of molecules into ions
D.
The increase in the mass of molecules
Correct Answer:
The separation or alignment of positive and negative charges within molecules
Explanation:
Molecular polarization occurs when positive and negative charges in molecules become slightly separated or permanent molecular dipoles become aligned.
2. What happens to a non-polar molecule placed in an external electric field?
A.
It becomes temporarily polarized
B.
It loses all its electrons
C.
It changes into a conductor
D.
It remains completely unaffected in every case
Correct Answer:
It becomes temporarily polarized
Explanation:
An external electric field can slightly separate the positive and negative charges of a non-polar molecule, producing an induced dipole.
3. A molecule with separate centers of positive and negative charge is called a:
A.
Permanent dipole
B.
Free electron
C.
Neutral ion
D.
Chargeless particle
Correct Answer:
Permanent dipole
Explanation:
A molecule having permanently separated centers of positive and negative charge behaves as a permanent electric dipole.
4. In an electric field, an induced molecular dipole is generally oriented:
A.
Along the electric field
B.
Perpendicular to the electric field
C.
Opposite to the electric field in every case
D.
Randomly, regardless of the field
Correct Answer:
Along the electric field
Explanation:
The induced dipole moment of a molecule is generally directed along the applied electric field.
5. Which type of molecule can have a permanent molecular dipole?
A.
Polar molecule
B.
Only a metallic molecule
C.
Only a molecule with no charges
D.
A molecule that cannot contain positive or negative charges
Correct Answer:
Polar molecule
Explanation:
Polar molecules have an uneven charge distribution and therefore possess a permanent dipole moment.
6. What is the main cause of induced molecular polarization?
A.
Displacement of positive and negative charges within a molecule
B.
Complete removal of all molecular charges
C.
Conversion of the molecule into a free ion
D.
Increase in the number of nuclei in the molecule
Correct Answer:
Displacement of positive and negative charges within a molecule
Explanation:
An external electric field produces a small relative displacement between the positive and negative charges of a molecule.
7. In the absence of an external electric field, the permanent dipoles of many polar molecules are usually:
A.
Randomly oriented
B.
All oriented in the same direction
C.
Completely destroyed
D.
Converted into free charges
Correct Answer:
Randomly oriented
Explanation:
Without an external field, thermal motion usually keeps permanent molecular dipoles randomly oriented.
8. When a polar insulating material is placed in an electric field, its molecules tend to:
A.
Become more aligned with the field
B.
Lose all their dipole moments
C.
Stop containing positive charges
D.
Turn into conducting molecules
Correct Answer:
Become more aligned with the field
Explanation:
The electric field exerts a turning effect on permanent molecular dipoles, causing them to tend toward alignment with the field.
9. What does the dipole moment of a polarized molecule indicate?
A.
The strength and direction of its molecular polarization
B.
The mass of the molecule only
C.
The number of neutrons in the molecule
D.
The temperature of the surrounding material only
Correct Answer:
The strength and direction of its molecular polarization
Explanation:
The electric dipole moment represents the magnitude and direction of the separation of positive and negative charges in a molecule.
10. If the external electric field is removed from a non-polar molecule, what usually happens to its induced polarization?
A.
It disappears
B.
It becomes permanently larger
C.
It changes the molecule into a permanent dipole in every case
D.
It causes the molecule to become a conductor
Correct Answer:
It disappears
Explanation:
The charge separation in an induced dipole is caused by the external field, so it generally vanishes when the field is removed.
Short Questions and Answers
Practice short questions and answers related to
Molecular Polarization
.
Short questions are currently unavailable for this page.