14
MCQ (Single Correct Answer)
Which of the following oxides shows electrical properties like metals?
A
$\mathrm{SiO}_2$
B
MgO
C
$\mathrm{SO}_2(\mathrm{~s})$
D
$\mathrm{CrO}_2$
15
MCQ (Single Correct Answer)
The lattice site in a pure crystal cannot be occupied by ........... .
A
molecule
B
ion
C
electron
D
atom
16
MCQ (Single Correct Answer)
Graphite cannot be classified as .......... .
A
conducting solid
B
network solid
C
covalent solid
D
ionic solid
17
MCQ (Single Correct Answer)
Cations are present in the interstitial sites in ......... .
A
Frenkel defect
B
Schottky defect
C
vacancy defect
D
metal deficiency defect
18
MCQ (Single Correct Answer)
Schottky defect is observed in crystals when ............ .
A
some cations move from their lattice site to interstitial sites
B
equal number of cations and anions are missing from the lattice
C
some lattice sites are occupied by electrons
D
some impurity is present in the lattice