THE SOLID STATE

JavaScript isn't enabled in your browser, so this file can't be opened. Enable and reload.

THE SOLID STATE

CLASS XII CHEMISTRY UNIT 1

NAME OF THE STUDENT *

NAME OF KV *

NAME OF REGION

1. Which of the following is an amorphous solid? *

1 point

(a) Graphite (C)

(b) Quartz glass (SiO2)

(d) Silico Carbide (SiC)

2. Which of the following statement is not true about amorphous solids? *

1 point

(a) On heating they may become crystalline at certain temperature

(b) They may become crystalline on keeping for long time.

(d) They are anisotropic in nature.

3. The sharp melting point of crystalline solids is due to____ *

1 point

(d) Different arrangement of constituent particles in different directions.

(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

4. Iodine molecules are held in the crystal lattice by __________ *

1 point

(a) London forces

(b) Dipole-Dipole interactions

(d) Coulombic forces

5. Which of the following is a network solid? *

1 point

(a) SO2 (Solid)

(b) I2

(d) H2O (Ice)

6. Graphite is a good conductor of electricity due to the presence of_____

1 point

(a) lone pair of electrons

(b) free valence electrons

(d) Anions

Clear selection

7. Cations are present in the interstitial sites in _______

1 point

(a) Frankel defect

(b) Schottky defect

(d) Metal deficiency defect

Clear selection

8. Schottky defect is observed in crystals when_______ *

1 point

(a) some cations move from their lattice site to interstitial sites.

(b) equal number of cations and anions are missing from the lattice.

(d) some impurity is present in the lattice.

Option 5

9. Which of the following point defects are shown by AgBr (s) crystals? (A) Schottky defect (B) Frenkel defect (C) Metal excess defect (D) Metal deficiency defect *

1 point

(a) (A) and (B)

(b) (C) and (D)

(d) (B) and (D)

10. Which kind of defects are introduced by doping. *

1 point

(a) Schottky defect

(b) Frenkel defect

(d) Electronic defect

11. Silicon doped with electron-rich impurity forms____ *

1 point

(a) p-type semiconductor

(b) n-type semiconductor

(d) insulator

12. Which of the following statement is not true? *

1 point

(a) Paramagnetic substances are weakly attracted by magnetic field.

(b) Ferromagnetic substances cannot be magnetized permanently.

(d) Pairing of electrons cancels their magnetic moment in the diamagnetic substances.

Option 5

13. The correct order of the packing efficiency in the different types of unit cells is_____ *

1 point

(a) fcc < bcc < simple cubic

(b) fcc > bcc > simple cubic

(d) bcc < fcc > simple cubic

14. Which of the following defects is also known as dislocation defect? *

1 point

(a) Frenkel defect

(b) Schottky defect

(d) Simple interstitial defect

15. The edge lengths of the unit cells in terms of the radius of the spheres constituting fcc, bcc and simple cubic unit cell are respectively____ *

1 point

(a) 2√2r, 4r/√3, 2r

(b) 4r/√3, 2√2r, 2r

(d) 2r, 4r/√3, 2√2r

16. Assertion: The total number of atoms present in a simple cubic unit cell is one. Reason: Simple cubic unit cell has atoms at its corners, each of which is shared between eight adjacent unit cells. *

1 point