Monday 19 April 2021

solid State (MCQ's)

    1. Which of the following is not feature of Crystalline solids?

A. Have sharp M.pt

B. Have anisotropic nature

C. Show isotropy

D. Have a long-range orderly arrangement

2. The Percentage of free space per unit cell in Primitive, FCC & BCC respectively is

A. 47.6%, 32% & 26%

B. 47.6%, 28%, 32%

C. 47.6%, 26% & 32%

D. NOTA

3. Edge length ratio of BCC to FCC is ------

4. Which of the following is correct about Orthogonal Crystal ?

A. Has 4 Bravais lattices

B. BaSO4, KNo3, K2SO4

C. α=β=γ=90O

D. All of the above

5. Coordination Number of NaCl, CsCl, ZnS, CaF2, Na2O are

A. 6:6, 8:8, 4:4, 8:4, 4:8

B. 6:6, 8:8, 4:4, 8:8, 4:4

C. Reverse of Option A

D. Reverse of Option B

6. Which of the following is correct about Voids size :-

A. Oct. Void = 0.414 X r

B. 0.225 X r = Tet. Void

C. Tri. Void= 0.115 X r

D. All of the above

7. The percentage efficiency of 2D- SCP & HCP is :-

A 52.4%, 74%              B. 47.6 % & 36 %

C. 47.6 % & 26%         D. 52.4% & 60.4%

8. What of the following is incorrect about some of ionic crystals

A. NaCl has 4:4 Coordination number

B. Flourite structure(CaF2, BaCl2, SrF2) has 8:4 Coordination number

c. Antiflourite ( Na2O, Li2O) has 4:8 Coordination number

D. Spinel has a Bivalent & Trivalent cation , Bivalent occupies 1/8 th tet. Voids while Oxide ions Occupies CCp . Trivalent occupies ½ of Oct. Voids. Ex ZnFe2O4

9.Which  of the following is not a spinel

A. MgFe2O4

B. ZnFe2O4

C. AlFe2O4

D. NaFe2O4

10. Schottky defect is characterized  by

A. Equal number of cation &  anion loss

B. Occurs in ionic compounds with Higher C.No. & having size of ions almost equal

C. Decreases the density of crystal

D. A type of vacancy defect that occurs In NaCl, CsCl, KCl , KBr & AgBr etc

E. All of the above

11. Greater the F-Centres, ----will be the intensity of Colour

A. Greater

B. Lesser

C. Can’t be predicted

D. Nothing to do with colour intensity

12. The Crystal that exhibit both Schottky & Frenkel defect

A. AgBr             B. AgCl

C. AgI                D. CsCl

13. superconductivity is all about :-

A. When substances offers zero resistance

B. Kammerlingh Onnes observed this phenomenon at 4K in Hg.

C. YBa2Cu3O7, Nb3Ge alloy, La1.25Ba0.15CuO4, (TMTSF)2 PF6 ( Tetra methyl tetra selena fulvalene )

Exhibit superconductivity 

D. All of the above

14. Solids that have net zero magnetic moment:-

A. Diamagnetic & antiferromagnetic substances

B. Paramagnetic & Ferromagnetic substances

C. Ferrimagnetic & Antiferromagnetic substances

D. Only Diamagnetic substances

15. The ferro, ferri & anti-ferro magnetic substances changes into Paramagnetic solids at a particular temperature called as Curie temperature, this is because of alignment of spins in one direction .Fe3O4( Ferrimagnetic) gets converted to paramagnetic at

A. 850K       B. 890 K     C. 900K       D. NOTA

16. Bethollides are :-

A. Non-stoichimetric solids having metal deficiency defect like Ni0.98 O

B. Stoichimetric solids with no defect

C. Solids that acts like pseudo gold

D. NOTA

 

17.  A unit cell of NaCl has four formula units. The edge length of the unit cell is 0.564 nm . What is the density of NaCl

A. 2.16 g/ml                   B. 2.16 kg/l  

C. 2.16 kg/ml                 D. NOTA

18. The diffraction of Barium with X-radiation of wavelength 2.29 A0 gives a first order reflection at 30o. What is the distance between diffracted planes

A. 2.29 A0       B) 1.29A0       C) 4.19 A0      D) NOTA

19. A metal crystallizes into two cubic phases FCC & BCC whose unit cell lengths are 3.5 & 3 AO respectively. Calculate the ratio of densities of FCC & BCC

A. 1.259/1   B. 1.315/2   C. 1.315/1   D. 1.328/2

20. Inverse spinel structure are

A. Just opposite in occupancy wrt normal spinel

B. have M2+ ions occupy at Oct. Voids while M3+ equally occupy Tet. & Oct. voids

C. Fe3O4 is inverse spinel

D. All of the above

21. The edge length of BCC unit cell is 390pm . If the cation radius is 150pm then the radius of anion is

A. 187.7 pm   B. 197.7 Pm   C. 170.9 pm D. 1.84.7 pm

22. The effective radius of an iron atom is 1.42 A0. It has a rock salt structure. calculate its density ( Fe=56)

A. 5.8g/ml      B. 6.8g/ml     C. 7.8g/ml   D. 4.8g/ml

23. A close packing structure of uniform spheres has the cell edge = 0.8 mm. Find the radius of molecules of it has A) SCC lattice B) FCC lattice & C) BCC lattice respt.

A. 0.4 mm, 0.2828mm &  0.3464mm

B. 0.4mm, 0.4364mm, 0.2828mm

C. 0.44mm, 0.2626mm, 0.3434mm

D. NOTA

24. The most unstable & unsymmetrical crystal system is

A. orthorhombic crystal

B. Triclinic crystal

C. Monoclinic crystal

D. NOTA

25. The most stable & symmetrical crystal system is

A. triclinic                       B. Cubic

C. Orthorhombic           D. Hexagonal

 

26. Intrinsic semiconductors are :-

A. Pure Ge & Si

B. P & n- type Semi conductors

C. Both A & B                 D. NOTA

27. n-type SC is observed when

A. When P is doped in Si

B. When Al is doped in Si

C. When both P & Al are doped in Si & Ge

D. NOTA

28. CCP has ---fold symmetry & HCP has ---fold of symmetry  

A. plane of Symmetry

B. 2 fold symmetry & 3 fold symmetry

C. 3 fold symmetry  &  6 fold symmetry

D. NOTA

29. The Coordination number & Packing efficiency of HCP( ABAB…type ) & CCP( ABCABC..) type of 3D crystal

A. 12 & 74 %                   B. 6 & 60.4%

C. 12 & 60.4%                 D NOTA

30. Radius ratio is ratio of radius of

A. cation to anion ‘

B. anion to cation

C. radius of both to cation

D. radius of any to sum of both

31.  The contribution of an atom per unit cell A) at corner of Hexagonal & B) Side of hexagonal is respt.

A. 1/6 & ½                    B. ½& 1/6

C. ¼ & 1                         D. 1/6 & 1/6

32. In a closed packed array of N spheres , the number of tetrahedral holes are

A. N        B. 2N         C. N/2       D. N/4

33. In a solid AB having NaCl structre, A atoms occupy the corners of the cubic unit cell. If all the face centered atoms along one of the axes are removed , then the resultant formula is

A. A3B4    B. A3B2    C. A3B3   D. A3B5

34. The Bragg’s equation is mathematically

A. nλ = 2dSinφ

B. nλ= dsin O

C. nλ= 2dtan φ

D. E= hv

 

 

 

 

 

 

 

 

 

 

 

 

 

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