#### 12th Standard Chemistry Solid State English Medium Free Online Test One Mark Questions with Answer Key 2020 - 2021

12th Standard

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Chemistry

Time : 00:20:00 Hrs
Total Marks : 20
20 x 1 = 20
1. An ionic compound AxBy crystallizes in fcc type crystal structure with B ions at the centre of each face and A ion occupying entre of the cube. the correct formula of AxBy is

(a)

AB

(b)

AB3

(c)

A3B

(d)

A8B6

2. Solid CO2 is an example of

(a)

Covalent solid

(b)

metallic solid

(c)

molecular solid

(d)

ionic solid

3. The composition of a sample of wurtzite is FeO0.931.00 what % of Iron present in the form of Fe3+?

(a)

16.05%

(b)

15.05%

(c)

18.05%

(d)

17.05%

4. CsCl has bcc arrangement, its unit cell edge length is 400pm, its inter atomic distance is

(a)

400pm

(b)

800pm

(c)

$\sqrt { 3 } \times 100pm$

(d)

$\left( \cfrac { \sqrt { 3 } }{ 2 } \right) \times 400pm$

5. The fraction of total volume occupied by the atoms in a simple cubic is

(a)

$\left( \cfrac { \pi }{ 4\sqrt { 2 } } \right)$

(b)

$\left( \cfrac { \pi }{ 6 } \right)$

(c)

$\left( \cfrac { \pi }{ 4 } \right)$

(d)

$\left( \cfrac { \pi }{ 3\sqrt { 2 } } \right)$

6.  if ‘a’ stands for the edge length of the cubic system ; sc , bcc, and fcc. Then the ratio of radii of spheres in these systems will be respectively

(a)

$\left( \cfrac { 1 }{ 2 } a;\cfrac { \sqrt { 3 } }{ 2 } a;\cfrac { \sqrt { 2 } }{ 2 } a \right)$

(b)

$\left( \sqrt { 1a } :\sqrt { 3a } :\sqrt { 2a } \right)$

(c)

$\left( \cfrac { 1 }{ 2 } a:\cfrac { \sqrt { 3 } }{ 4 } a:\cfrac { 1 }{ 2\sqrt { 2 } } a \right)$

(d)

$\cfrac { 1 }{ 2 } a:\sqrt { 3 } a:\cfrac { 1 }{ \sqrt { 2 } } a$

7. The cation leaves its normal position in the crystal and moves to some interstitial position, the defect in the crystal is known as

(a)

Schottky defect

(b)

F center

(c)

Frenkel defect

(d)

non-stoichiometric defect

8. The crystal with a metal deficiency defect is

(a)

NaCl

(b)

FeO

(c)

ZnO

(d)

KCl

9. In which of the following arrangements, octahedral voids are formed?

(a)

fcc

(b)

bcc

(c)

simple cubic

(d)

hcp

10. Which of the following is characteristic of ionic solids?

(a)

Very low value of electrical conductivity in the molten state

(b)

Brittie nature

(c)

Very strong forces of attractions

(d)

Anisotropic nature

11. What is the relation between diamond and graphite?

(a)

Polymorphous

(b)

Isomer

(c)

Isotope

(d)

Isomorphous

12. A binary solid A+B- has a structure with B- ions constituting the lattice and A+ ions occupying 25% tetrahedral holes. Formula of the solid is

(a)

A2B

(b)

AB2

(c)

AB

(d)

AB4

13. Which one of the following crystal has 8: 8 structure?

(a)

MgF2

(b)

CsCl

(c)

KCl

(d)

NaCl

14. Which type of solids will have the highest melting point?

(a)

Ionic crystals

(b)

Network covalent solid

(c)

Molecular solids

(d)

Metallic crystals

15. Three atoms P, Q and R crystallize in a cubic solid lattice having P atom at corners Q atom at body centre and R atom at the face centres. Identify formula of the compound.

(a)

PQR

(b)

PQR2

(c)

PQR3

(d)

P3QR

16. The force that binds a metal ion to a number of electrons within its sphere of influence is known as__________ bond.

(a)

covalent

(b)

ionic

(c)

metallic

(d)

co-ordinate

17. In edge centred lattice, an atom in the edge is shared by__________

(a)

4 unit cell

(b)

12 unit cell

(c)

2 unit cell

(d)

8 unit cell

18. The size of the anion in Frenkel defect crystal is_______.

(a)

larger than the cation

(b)

smaller than the cation

(c)

equal in size with cation

(d)

both are larger in size

19. ABAB type of packing is called _________.

(a)

hexagonal close packing

(b)

cubic close packing

(c)

tetragonal close packing

(d)

none of the above

20. The coordination number of each sphere in body centred cubic packing is __________.

(a)

2

(b)

4

(c)

6

(d)

8