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Solid States

1. Silver crystallizes in FCC lattice. If edge length of unit cell is 4.077x 10^-8 cm and density is 10.5 g/cm³ , calculate atomic mass of silver.
2. A cubic solid is made of two elements P & Q. Atoms Q are at the corners of the cube and P are at the body center. What is the formula of the compound? What are the Co-ordination numbers of P & Q?
3. If the radius of octahedral void is ‘r’ and the radius of atoms in close packing is R, derive a relation between r & R.
4. Formula mass of NaCl is 58.45 g/mol and density of its pure form is 2.167 g/cm³. Average distance between adjacent sodium and chloride ions in the crystal is 2.814x10^-8 cm.
   Calculate Avogadro constant.
   M =5 8.45 g/mol
   ρ = 2.167 g/cm³
5. Analysis shows that nickel oxide has formula Ni_0.98 O_1.00. What fractions of Nickel exist as Ni²⁺ and Ni³⁺ ion?
6. If the radius of the Bromide ion is 0.182 nm, how large a cation can fit in each of the tetrahedral hole?.
7. Classify each of the following as p-type and n-type semiconductors.
   i) Ge doped with in : Ans : p-type
   ii) B Doped with Si Ans : n-type
8. Aluminium crystalises in a cubic close packed structure. Its’ metallic radius is 125 pm.
   (a) What is the length of the side of the unit cell.
   (b) How many unit cells are there in 1cm³ of aluminium
9. If NaCl is doped with 10^-3 mol% SrCl₂ , what is the concentration of cation vacancies
10. Calculate the value of Avogadro constant from the following data. Density of
    NaCl = 2.165 g/cm³. Distance b/w Na⁺ & Cl^- is 281 pm

1. Atomic Structure and Chemical Bonding
2. Solid States
3. Solutions
4. Thermodoynamics
5. Chemical Kinetics
6. Nuclear Chemistry
7. Polymers
8. Biomolecules
9. Chemistry In Every Day Life