5
MCQ (Single Correct Answer)
Which of the following is true about the value of refractive index of quartz glass?
A
 Same in all directions
B
 Different in different directions
C
 Cannot be measured
D
 Always zero
6
MCQ (Single Correct Answer)
Which of the following statement is not true about amorphous solids?
A
 On heating they may become crystalline at certain temperature
B
 They may become crystalline on keeping for long time
C
 Amorphous solids can be moulded by heating
D
 They are anisotropic in nature
7
MCQ (Single Correct Answer)
The sharp melting point of crystalline solids is due to ..........
A
 a regular arrangement of constituent particles observed over a short distance in the crystal lattice
B
 a regular arrangement of constituent particles observed over a long distance in the crystal lattice
C
 same arrangement of constituent particles in different directions
D
 different arrangement of constituent particles in different directions
8
MCQ (Single Correct Answer)
Iodine molecules are held in the crystals lattice by ...........
A
 London forces
B
 dipole-dipole interactions
C
 covalent bonds
D
 coulombic forces
9
MCQ (Single Correct Answer)
Which of the following is a network solid?
A
 $\mathrm{SO}_2$ (solid)
B
 $\mathrm{I}_2$
C
 Diamond
D
 $\mathrm{H}_2 \mathrm{O}$ (ice)