Study Material
Solid State
Very Short Answer Questions
Q1. Define the term amorphous.
Q2. What makes a glass different from quartz?
Q3. Classify the following solids as ionic, metallic, molecular, covalent network or amorphous. (1) $\ce{Si}$ (11)$\ce{I2}$ (iii) $\ce{P4}$(iv) $\ce{Rb}$ (v) SiC (vi) LiBr (vii) Ammonium Phosphate $\ce{(NH4)3PO4}$ (viii) Plastic (ix) graphite (x)tetra phosphorous decoxide (xi) brass
Q4. What is meant by the term coordination number?
Q5. What is the coordination number of atoms in a cubic close-pack structure?
Q6. What is the coordination number of atoms in a body-centered cubic structure?
Q7. Stability of a crystal is reflected in the magnitude of its melting point. Comment
Q8. How are the intermolecular forces among the molecules affect the melting point?
Q9. How do you distinguish between hexagonal close-packing and cubic close- packing structures?
Q10. How do you distinguish between crystal lattice and unit cell?
Q11. How many lattice points are there in one unit cell of face-centered cubic lattice?
Q12. How many lattice points are there in one unit cell of face-centered tetragonal lattice?
Q13. How many lattice points are there in one unit cell of body centered cubic lattice?
Q14. What is a semi conductor?
Q15. What is Schottky defect?
Q16. What is Frenkel defect?
Q17. What is interstitial defect?
Q19. Explain Ferromagnetism with suitable example.
Q20. Explain Paramagnetism with suitable example.
Q21. Explain Ferromagnetism with suitable example.
Q22. Explain Antiferromagnetism with suitable example.
Q23. Why X-rays are needed to probe the crystal structure?
Q1. Explain similarities and differences between metallic and ionic crystals.
Q2. Explain why ionic solids are hard and brittle.
Q3. Calculate the efficiency of packing in case of a metal of simple cubic crystal.
Q4. Calculate the efficiency of packing in case of a metal of body-centered cubic crystal.
Q5. Calculate the efficiency of packing in case of face-centered cubic crystal.
Q6. A cubic solid is made of two elements P and Q. Atoms of are at the corners of the cube and P at the body-centre. What is the formula of the compound? What are the coordination numbers of P and Q?
Q7. If the radius of the octahedral void is 'r' and radius of the atoms in close- packing is 'R', derive relation between r and R.
Q8. Describe the two main types of semiconductors and contrast their conduction mechanism.
Q9. Classify each of the following as either a p-type or a n-type semiconductor. 1. $\ce{Ge}$ doped with In 2.$\ce{Si }$doped with B.
Q10. Analysis shows that nickel oxide has the formula $\ce{Ni_{0.98}.O_{1.00}}$,what fractions of nickel exist as $\ce{Ni^{2+} and Ni^{+3}}$ ions?
Q11. Gold (atomic radius = 0.144nm) crystallizes in a face centered unit cell. What is the length of a side of the unit cell?
Q12. In terms of band theory, what is the difference between a conductor and an insulator?
Q13. In terms of band theory, what is the difference between a conductor and a semiconductor?
Q14. If$\ce{ NaCl}$ is doped with $ 1 \times 10^{-3}$ mol percent of $\ce{SrCl2}$what is the concentration of cation vacancies?
Q15. Derive Bragg's equation.
Q1. How do you determine the atomic mass of an unknown metal if you know its density and dimension of its unit cell? Explain
Q2. Silver crystallizes in $\ce{FCC}$ lattice. If edge of the cell is $\ce{4.07 \times 10^{-8}}$ cm and density is$\ce{10.5 \, gcm^{-3}}$. Calculate the atomic mass of silver.
Q3. Niobium crystallizes in body-centered cubic structure. If density is 8.55 $ gcm^{-3}$, calculate atomic radius of niobium using its atomic mass$\ce{ 93U}$.
Q4. Copper crystallizes into a fec lattice with edge length $\ce{3.61x10^{-8}}$ cm.Show that the calculated density is in agreement with its measured value of 8.92 $ gcm^{-3}$,.
Q5. Ferric oxide crystallizes in a hexagonal close-packed array of oxide ions with two out of every three octahedral holes occupied by ferric ions. Derive the formula of ferric oxide.
Q6. Aluminum crystallizes in a cubic close packed structure. Its metallic radius is 125 pm. (1) what is the length of the side of the unit cell. [Ans: 354 pml (ii) How many unit cells are there in 1.00 cm³ of aluminum?
Q7. How do you obtain the diffraction pattern for a crystalline substance?