Solved Papers · Stars mark importance
PYQ Solutions
Previous-year questions on Structure and Properties of Solids, solved step by step in simple exam-ready language. Every question is marked ⭐ 1–5 for importance, with the exact years it appeared.
⭐ Importance rated📅 Year-wise✍️ Exam-ready answers
📋
About these papers — read first
Every question below is solved in full inside its chapter's PYQ Zone — this page is your finder. We read all 50 pages of the new B.Sc. papers (CC-6, CC-9, CC-11, DSE-1, DSE-4 · 2018–2025) plus all 60 pages of the M.Sc. papers (MSCH/MCHEM · 2020–2024) with AI vision, and kept only the questions that belong to the Structure and Properties of Solids syllabus. Each entry shows the exact year, B.Sc./M.Sc. paper, question number and marks; questions that repeated across years say so.
| Papers scanned | Years | Relevant solids questions |
|---|---|---|
| B.Sc. CC-6 (Inorganic Chemistry-II) | 2018, 2020, 2021, 2022 | Defects, lattice energy, radius ratio, semiconductors |
| B.Sc. DSE-1 (Advanced Physical Chemistry) | 2019–2024 | Bravais lattices, Miller indices, Bragg, density, heat capacity, residual entropy |
| B.Sc. CC-11 (Inorganic Chemistry-IV) | 2019–2024 | Spinels, magnetic solids |
| B.Sc. CC-9 (Inorganic Chemistry) | 2019, 2022, 2023 | Chain silicates, graphite vs BN |
| B.Sc. DSE-4 (Industrial Inorganic Materials) | 2020–2025 | No direct solids questions found |
| M.Sc. MSCH-104 (Physical General-I) | 2022–2024 | Cube symmetry, density of states, residual entropy of CO |
Hottest repeats: Born–Haber/lattice energy (2018, 2020, 2021, 2022) · Einstein heat capacity (2019, 2020, 2022, 2024) · superexchange (2019, 2022, 2023) · spinels (2020, 2021, 2024) · ZnO heating (2021, 2022). ⭐⭐⭐⭐⭐
- Q1(e) — “What are the dimensional characteristics of a triclinic Bravais lattice?”
2024 · B.Sc. DSE-1 · 2 marks - Q1(a) — “Name the different types of Bravais lattices that can be obtained for a tetragonal crystal. Find the number of atoms per unit cell for a body-centred tetragonal crystal.”
2023 · B.Sc. DSE-1 · 2 marks - Q2(a)(i) — “Five-fold rotational axis of symmetry is impossible in case of a crystal. Justify.”
2019 · B.Sc. DSE-1 · 3 marks - Q2(b)(ii) — “By means of lattice diagram, show the possible Bravais lattices in case of an orthorhombic system of crystals.”
2019 · B.Sc. DSE-1 · 2 marks - Q2(a)(i) — Justify or criticize: “Miller indices of a crystal face actually refer to a class of faces.”
2024 · B.Sc. DSE-1 · 2 marks - Q2(a)(ii) — “Find the intercepts made on the three axes by the first (most near to the origin) two planes among the class represented by the Miller indices (2̄10). Depict the two planes.”
2024 · B.Sc. DSE-1 · 3 marks - Q10(b) — “Designate the Miller indices of all the six faces of a simple cubic unit cell with appropriate diagram.”
2021 · B.Sc. DSE-1 · 5 marks - Q3(c)(ii) — “Find out the intercepts on the crystallographic axes of a plane with Miller indices (2 0 1) with unit cell dimensions a = 6·8 nm, b = 8·6 nm and c = 4·6 nm.”
2022 · B.Sc. DSE-1 · 2 marks - Q3 — “Calculate the percentage of void space in a fcc unit cell. Find out the Miller indices of the plane that makes intercepts ½, 2 and 3/2 multiples of unit distances on the three axes.”
2020 · B.Sc. DSE-1 · 5 marks - Q2 — “Derive the expression of interplanar distance for an orthorhombic system. Calculate the coordination number of an atom in 3-D close packed structure.”
2020 · B.Sc. DSE-1 · 5 marks - Q1(c) — “Find the symmetry elements and operations of a cube.”
2022 · M.Sc. MSCH-104 · 3 marks - Q3(a)(i) — “Derive the Bragg's equation of diffraction of X-ray on a crystal. State the condition for the validity of this equation.”
2023 · B.Sc. DSE-1 · 3 marks - Q3(a)(ii) — “In X-ray diffraction, KCl shows SC pattern though it is a FCC lattice. — Comment.”
2023 · B.Sc. DSE-1 · 2 marks - Q3(a)(i) — “Explain why a crystal acts as a three-dimensional diffraction grating for X-rays.”
2024 · B.Sc. DSE-1 · 2 marks - Q3(a)(ii) — “What do you mean by order of reflection? What is its significance?”
2024 · B.Sc. DSE-1 · 2 marks - Q3(a)(iii) — “Find the minimum interplanar distance for a crystal to produce a diffraction spectra for a given radiation.”
2024 · B.Sc. DSE-1 · 2 marks - Q1(f) — “What is the minimum measurable value of spacing between crystal planes when the wavelength of 1·67 Å is employed?”
2022 · B.Sc. DSE-1 · 2 marks - Q1(h) — “Why are radio waves considered to be unsuitable for determining crystal structure?”
2022 · B.Sc. DSE-1 · 2 marks - Q2(a)(i) — “The molar volume of KCl is 1·3 times that of NaCl. The glancing angle for the 1st order Bragg reflection from the (200) plane of NaCl is 5·9°. Find the glancing angle from the (200) plane of KCl.”
2023 · B.Sc. DSE-1 · 3 marks - Q3(b) — “Determine the highest order of reflection that can be observed in Bragg's reflection from a solid employing X-ray spectroscopic technique.”
2021 · B.Sc. DSE-1 · 5 marks - Q1(f) — “Show that the interplanar distance for a cubic crystal can never be a/√7, where 'a' is the length of an edge of the cube.”
2024 · B.Sc. DSE-1 · 2 marks - Q2(d)(i) — “Show that the distance of separation between the successive (hk) planes in a two dimensional square lattice is a/√(h²+k²), where 'a' is the unit distance along X and Y axes.”
2019 · B.Sc. DSE-1 · 3 marks - Q3(b)(ii) — “A metal forms a cubic lattice with edge length 6·18 Å. Find the radius of an atom of the metal (taking an atom to be spherical) if the density of the metal be 1·87 g cm⁻³ & the mass of one atom of it be 132·9 a.m.u.”
2024 · B.Sc. DSE-1 · 4 marks - Q3(b)(iii) — “Aluminium (At. wt. 27, density 2·69 g cm⁻³) crystallises with FCC lattice. What is the distance of closest approach of Al-atoms in the crystal?”
2023 · B.Sc. DSE-1 · 3 marks - Q3(d)(i) — “Ag is known to crystallise in f.c.c. form and the distance between the nearest neighbour atoms is 2·87 Å. Calculate the density of Ag [At. Wt. of Ag = 108].”
2022 · B.Sc. DSE-1 · 3 marks - Q3(a) — “Europium (Atomic weight: 152 g·mol⁻¹) crystallizes in a bcc lattice. The density of Europium (Eu) is estimated to be 5.26 g·cm⁻³. Calculate the radius of Eu atom from above information.”
2021 · B.Sc. DSE-1 · 5 marks - Q3(c)(i) — “Insulin forms crystals of orthorhombic type with a = 13 nm, b = 7·48 nm and c = 3·09 nm. If the density of the crystal is 1·315 × 10³ kg/m³, and there are 66 insulin molecules per unit cell, what is the molar mass of insulin?”
2022 · B.Sc. DSE-1 · 3 marks
- Q1(b) — “Mention two differences between tetrahedral void and octahedral void.”
2023 · B.Sc. DSE-1 · 2 marks - Q2 — “What is the key difference between hcp and ccp structures? Suppose X atoms form a close packed lattice structure, where Y atoms (smaller than X atoms) have to be incorporated without disturbing the close-packed lattice. Write down the formula of the compounds with proper justification when (i) Y atoms are occupied in all tetrahedral voids; (ii) Y atoms are occupied in half of the tetrahedral voids; (iii) Y atoms are occupied in all the octahedral voids; and (iv) Y atoms are occupied in half of the octahedral voids. Mention the limiting radius in each case of Y atoms in regard to that of X atoms, so that Y atoms fit perfectly either in tetrahedral voids or in octahedral voids.”
2021 · B.Sc. DSE-1 · 5 marks - Q3(d)(iv) — “Calculate the packing efficiency of fcc lattice.”
2018 · B.Sc. CC-6 · 2 marks - Q2(b)(i) — “Calculate the percentage of space occupied in an atomic BCC lattice.”
2023 · B.Sc. DSE-1 · 3 marks - Q2(b) — “What do you mean by radius ratio principle? What information can be obtained from it? Find out the limiting radius ratio for tetrahedral and cubic coordination.”
2022 · B.Sc. CC-6 · 5 marks
- Q3(b)(i) — “What do you mean by lattice energy of an ionic crystal? Calculate the lattice energy of NaCl using the following data: Madelung Constant (A) = 1·748, Equilibrium ionic distance = 2·79 Å, Born Exponent = 8·0, Electronic charge = 4·8×10⁻¹⁰ esu.”
2022 · B.Sc. CC-6 · 4 marks - Q2(d)(i) — “What is Madelung's constant? What is its significance?”
2018 · B.Sc. CC-6 · 3 marks - Q7 — “What is Born-Haber Cycle? Calculate the lattice energy of NaCl crystal from the following data by use of Born-Haber Cycle. Sublimation energy (S) = 108.7 kJ mol⁻¹, Dissociation energy for Cl₂ (D) = 225.9 kJ mol⁻¹, Ionization potential of Na(g) (I) = 489.5 kJ mol⁻¹, Electron affinity of Cl(g) (E) = −351.4 kJ mol⁻¹, Enthalpy of formation of NaCl (ΔHf) = −414.2 kJ mol⁻¹.”
2021 · B.Sc. CC-6 · 5 marks - Q7 — “Define lattice energy. Establish Born-Haber cycle for the formation of MgS(s) starting from Mg(s) and S₈(s), and hence calculate the electron affinity of S(g) for the S(g) + 2e⁻ ⟶ S²⁻(g) reaction using the thermochemical data given below: Enthalpy of formation = −345 kJ mol⁻¹, Enthalpy of sublimation of Mg(s) = 153 kJ mol⁻¹, Sum of 1ˢᵗ and 2ⁿᵈ ionization potentials of Mg(g) = 2187 kJ mol⁻¹, Enthalpy of atomization of S₈(s) = 559 kJ mol⁻¹, Lattice energy of MgS(s) = −2948 kJ mol⁻¹.”
2020 · B.Sc. CC-6 · 5 marks - Q3(a)(ii) — “Calculate the heat of formation (ΔHf) of KF from its elements from the following data by the use of Born-Haber cycle. Sublimation energy of K(s) = 87·8 kJ mol⁻¹, Dissociation energy of F₂(D) = 158·9 kJ mol⁻¹, Ionization energy of K(g)(I) = 414·2 kJ mol⁻¹, Electron affinity for F(g)(E) = −334·7 kJ mol⁻¹, Lattice energy of KF (U₀) = −807·5 kJ mol⁻¹.”
2018 · B.Sc. CC-6 · 3 marks
- Q3(a)(ii) — “Describe the normal and inverse spinel structures with suitable examples of each.”
2020 · B.Sc. CC-11 · 2+2 marks - Q3(a)(ii) — “Which of the following compounds are normal and which are inverse spinels? Justify your answer. Co₃O₄ and NiCr₂O₄.”
2021 · B.Sc. CC-11 · 2+2 marks - Q3(a)(ii) — “Give the spinel structures of Mn₃O₄ and Fe₃O₄, with proper justification.”
2024 · B.Sc. CC-11 · 4 marks - Q3(c)(iii) — “What are pyroxene and amphibole? Illustrate structurally.”
2019 · B.Sc. CC-9 · 2 marks
- Q3(d)(iii) — “What are stoichiometric defects in crystals? Discuss them with examples.”
2018 · B.Sc. CC-6 · 4 marks - Q3(a) — “What are Frenkel and Schottky defects? What kind of defect is exhibited when ZnO is heated? Explain.”
2021 · B.Sc. CC-6 · 4 marks - Q1(h) — “ZnO is white when cold and yellow when hot. Explain.”
2022 · B.Sc. CC-6 · 2 marks - Q1(f) — “Explain the origin of residual entropy of H₂O(s).”
2019 · B.Sc. DSE-1 · 2 marks
- Q3(d)(ii) — “State the band theory of metals and distinguish between conductors, insulators and semiconductors on its basis.”
2018 · B.Sc. CC-6 · 4 marks - Q2(d)(ii) — “What is n-type semiconductor? Give example.”
2018 · B.Sc. CC-6 · 2 marks - Q3(c) — “How does the electrical conductivity vary with temperature in metals and in semiconductors? Explain.”
2021 · B.Sc. CC-6 · 3 marks - Q6(a) — “What is density of states? Derive expressions for density of states for 0D, 1D and 2D systems.”
2023 · M.Sc. MSCH-104 · 3½+… [unclear] - Q2(a)(ii) — “Graphite conducts electricity but boron nitride does not, though both have layered structure. Explain.”
2023 · B.Sc. CC-9 · 2 marks - Q6 — “Derive an expression for molar heat capacity of a solid following Einstein's model. State its limitations.”
2019 · B.Sc. DSE-1 · 5 marks
- Q4(a) — “What do you mean by magnetically dilute and magnetically concentrated compounds? Give examples of each.”
2019 · B.Sc. CC-11 · 4 marks - Q4(b) — “What is superexchange interaction? Explain with a suitable example.”
2019 · B.Sc. CC-11 · 4 marks - Q4(a) — “Distinguish between ferromagnetism and antiferromagnetism. What is the significance of the sign of the exchange integral J?”
2022 · B.Sc. CC-11 · 4 marks - Q4(d) — “What are Curie point and Néel point?”
2022 · B.Sc. CC-11 · 2 marks - Q4(e) — “Comment on the magnetic behaviour of solid AgO.”
2022 · B.Sc. CC-11 · 2 marks - Q4(c) — “What is quenching of orbital magnetic moment? Explain.”
2023 · B.Sc. CC-11 · 3 marks - Q4(c) — “Write down the SI units of magnetic susceptibility, magnetic moment and magnetisation.”
2019 · B.Sc. CC-11 · 2 marks
- Q3(c)(iv) — “What are clathrates? Give example.”
2019 · B.Sc. CC-9 · 2 marks - Q3(c)(v) — “What is zone refining? Mention its application.”
2019 · B.Sc. CC-9 · 2 marks