Topic wise important and hots questions from Solid state

                                                  Class –XII Solid State                                                              

S.No.	Chapter Name	Topic-Concept Name	VSA/SA/long answer question
1	Solid State	General Characteristics of Solid State	VSA-36 SA TYPE-I (2MARKS)-18 SA TYPE-II (3MARKS)-8   Note - This time (Session2020-21), CBSE has removed Electrical Properties, Magnetic Properties from board exam. So, you can leave these topic to get good score for board exams
		Amorphous and Crystalline Solids
		Classification of Crystalline Solids
		Crystal Lattices and Unit Cells
		Number of Atoms in A Unit Cell
		Close Packed Structures
		Packing Efficiency
		Calculations Involving Unit Cell Dimensions
		Imperfections in Solids
		Electrical Properties
		Magnetic Properties

VERY SHORT ANSWER TYPE QUESTIONS (1 Mark) 

S.No.	Topic-Concept Name	VSA (1 Marks)
1	Close Packed Structures	What is the coordination number of each type of ions in a rock-salt type crystal structure?
2	Number of Atoms in A Unit Cell	What is the total number of atoms per unit cell in a face-centred cubic (fcc) structure?
3	Magnetic Properties	What type of substances exhibit anti-ferromagnetism?
4	Electrical Properties	Define the ‘forbidden zone’ of an insulator.
5	Imperfections in Solids	Which crystal defect lowers the density of a solid?
6	Electrical Properties	Name an element with which silicon may be doped to give a p-type semiconductor.
7	Imperfections in Solids	Which point defect in crystals does not alter the density of the relevant solid?
8	Imperfections in Solids	Which point defect in its crystal units increases the density of a solid?
9	Electrical Properties	How do metallic and ionic substances differ in conducting electricity?
10	Crystal Lattices and Unit Cells	What is the number of atoms in a body-centred cubic unit cell of a crystal?
11	Classification of Crystalline Solids	Write a feature which will distinguish a metallic solid from an ionic solid.
12	Classification of Crystalline Solids	What type of interactions hold the molecules together in a polar molecular solid?
13	General Characteristics of Solid State	Account on the following- a) Liquids and gases categorized as fluid b) Solids incompressible
14	Electrical Properties	What type of semiconductor is obtained when silicon is doped with arsenic?
15	Classification of Crystalline Solids	Write a distinguishing feature of metallic solids?
16	Crystal Lattices and Unit Cells	What is the number of atoms in a unit cell of a simple cubic crystal?
17	Amorphous and Crystalline Solids	‘Crystalline solids are anisotropic in nature.’ What does this statement mean?
18	Crystal Lattices and Unit Cells	Define terms unit cell in relation to crystalline solids:
19	Electrical Properties	What is meant by an ‘intrinsic semiconductor’?
20	Electrical Properties	What is meant by ‘doping’ in a semiconductor?
21	Classification of Crystalline Solids	Write a point of distinction between a metallic solid and an ionic solid other than metallic lustre.
22	Electrical Properties	How may the conductivity of an intrinsic semiconductor be increased?
23	Magnetic Properties	Define paramagnetism with an example.
24	Imperfections in Solids	What type of point defect is produced when AgCl is doped with CdCl2?
25	Imperfections in Solids	What type of stoichiometric defect is shown by AgCl?
26	Magnetic Properties	What type of substances would make better permanent magnets, ferromagnetic or ferrimagnetic?
27	Classification of Crystalline Solids	Which group of solids is electrical conductors, as well as malleable and ductile?
28	Classification of Crystalline Solids	Why glass is considered a supercooled liquid?
29	Close Packed Structures	What is the two-dimensional coordination number of a molecule in a square close-packed layer?
30	Imperfections in Solids	Define F-centers.
31	Magnetic Properties	What happens when a ferromagnetic substance is subjected to high temperature?
32	Amorphous and Crystalline Solids	Define term amorphous amorphous.
33	Close Packed Structures	What are the  co-ordination  numbers  of  octahedral  voids  and  tetrahedral voids ?
34	Imperfections in Solids	CaCl2 will introduce Schottky defect if added to AgCl crystal. Explain.
35	Amorphous and Crystalline Solids	What is the difference between glass and quartz do both contain silicate unit?
36	Amorphous and Crystalline Solids	Which property of glass enables it to be molded and blown in to various shapes

 

 SHORT ANSWER-I TYPE QUESTIONS (2 Marks)

 

S.No.	Topic-Concept Name	SA (2 Marks)
37	Calculations Involving Unit Cell Dimensions	Silver crystallizes with face-centered cubic unit cells. Each side of the unit cell has a length of 409 pm. What is the radius of an atom of silver? (Assume that each face atom is touching the four corner atoms.)
38	Calculations Involving Unit Cell Dimensions	Explain how you can determine the atomic mass of an unknown metal if you know its mass density and the dimensions of unit cell of its crystal.
39	Packing Efficiency	Calculate the packing efficiency of a metal crystal for a simple cubic lattice.
40	Imperfections in Solids	Account for the following: Schottky defects lower the density of related solids. Conductivity of silicon increases on doping it with phosphorus.
41	Calculations Involving Unit Cell Dimensions	(a) Why does presence of excess of lithium makes LiCl crystals pink? (b) A solid with cubic crystal is made of two elements P and Q. Atoms of Q are at the corners of the cube and P at the body-centre. What is the formula of the compound?
42	Classification of Crystalline Solids	Classify the following solids with appropriate reason: - (A) Argon (B) Sulphur dioxide
43	Close Packed Structures	Out of squre close packing hexagonal close packing which one is more stable and why in two dimensions.
44	Close Packed Structures	What is the relation between? - A). Total number of well packed particles, number of octahedral and number of tetrahedral voids in a unit cell. B). Edge length of (a) and radius of constituent particle in (r) body centered unit cell.
45	Imperfections in Solids	Account on the following: - A). ZnO on heating turn white to yellow. B). d-block elements show metal deficiency defect.
46	Imperfections in Solids	Analysis shows that a metal oxide has  the  empirical  formula  M0.98O1.00. Calculate the percentage of M2+ and M3+ ions in the crystal.
47	Imperfections in Solids	Explain how electrical neutrality is maintained in compounds showing Frenkel and Schottky defect.
48	Electrical Properties	In terms of band theory, what is the difference between a conductor, an insulator and a semi-conductor?
49	Electrical Properties	The electrical conductivity of a metal decreases with rise in temperature while that of a semi-conductor increases. Explain.
50	Magnetic Properties	What type of substances would make better permanent magnets, ferromagnetic or ferromagnetic? Why?
51	Calculations Involving Unit Cell Dimensions	In compound atoms of element Y forms ccp lattice and those of element X occupy 2/3rd of tetrahedral voids. What is the formula of the compound?
52	Amorphous and Crystalline Solids	Some of the very old glass objects appear slightly milky instead of being transparent.
53	Imperfections in Solids	Ionic solids which have an ionic vacancy due to metal excess defect develop colour explain with the help of a suitable example
54	Close Packed Structures	What is AB....AB....AB..... type of arrangement and ABC......ABC......ABC. type of arrangement. Write the coordination number for each.

 

SHORT ANSWER-II TYPE QUESTIONS (3 Marks)

 

S.No.	Topic-Concept Name	SA TYPE-II (3 Marks)
55	Electrical Properties	What is a semiconductor? Describe the two main types of semiconductors and explain mechanisms for their conduction
56	Imperfections in Solids	How would your account for the following? a. Frenkel defects are not found in alkali metal halides. b. Schottky defects lower the density of related solids. c. Impurity doped silicon is a semiconductor.
57	Magnetic Properties	Explain the following properties giving suitable examples: a. Ferromagnetism b. Para magnetism c. Ferrimagnetism
58	Calculations Involving Unit Cell Dimensions	Iron has a body-centered cubic unit cell with a cell edge of 286.65 pm. The density of iron is 7.87g cm–3. Use this information to calculate Avogadro’s number (At. mass of Fe = 56g  mol–11).
59	Calculations Involving Unit Cell Dimensions	The well-known mineral fluorite is chemically calcium fluoride. It is known that in one-unit cell of this mineral there are 4 Ca2+ ions and 8 F– ions and that Ca2+ ions are arranged in a fcc lattice. The F– ions fill all the tetrahedral holes in the face centred cubic lattice of Ca2+ ions. The edge of the unit cell is 5.46 × 10–8 cm in length. The density of the solid is 3.18 g cm–3. Use this information to calculate Avogadro's number (Molar mass of CaF2 = 78.08 g mol–1)
60	Calculations Involving Unit Cell Dimensions	The density of copper metal is 8.95 g cm -3. If the radius of copper atom is 127.8 pm, is the copper unit cell a simple cubic, a body-centered cubic or a face-centered cubic structure? (Given: At. mass of Cu=63.54 g mol -1 and NA = 6.022 × 1023 mol -1)
61	Calculations Involving Unit Cell Dimensions	Aluminium crystallizes in a cubic close-packed structure. Radius of the atom in the metal is 125 pm. (i) What is the length of the side of the unit cell? (ii) How many unit cells are there in 1 cm3 of aluminium?
62	Crystal Lattices and Unit Cells	Define: - a. Lattice point b. Crystal lattice c. Bravais lattice