131. |
The atoms of element Y form hexagonal close packing and the atoms of element X occupies portion of the number of tetrahedral voids. Write the formula of the compound formed by X and Y.
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Answer:
Option (c) |
132. |
A particular solid is very hard and has a high melting point. In solid state it is a non conductor and its melt is a conductor of electricity. Classify the solid.
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Answer:
Option (b) |
133. |
Tetragonal crystal system has the following unit cell dimensions.
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Answer:
Option (b) |
134. |
Total volume of atoms present in a face-centred cubic unit cell of a metal is (r is radius of atom.)
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Answer:
Option (a) |
135. |
The crystal system of a compound with unit cell dimensions a = 0.387, b = 0.387, c = 0.504 and α = β = 90°and γ = 120° is
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Answer:
Option (b) |
136. |
The number of atoms contained in one face-centred cubic unit cell of monoatomic substance is
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Answer:
Option (c) |
137. |
In a face-centred cubic lattice, the number of nearest neighbours for a given lattice point is
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Answer:
Option (c) |
138. |
An oxide of transition metal that has conductivity as well as appearance like that of copper is
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Answer:
Option (c) |
139. |
The fraction of total volume occupied by the atoms present in a simple cube is
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Answer:
Option (a) |
140. |
Assertion (A) : No compound has both Schottky and Frenkal defects.
Reason (R) : Both defects change the density of the solid.
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Answer:
Option (d) |