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CBSE Class 12 Chemistry Test – Solid State

MM : 25 TIME : 40 MIN.
1. Give an example of ionic compound which show Frenkel defect.
2. What type of semiconductor is obtained when silicon is doped with Arsenic?
3. How do metallic and ionic substances differ in conducting electricity ?
4. How are the following properties of the crystals affected by Schottky and Frenkel defects
(i) Density (ii) Electrical Conductivity
5. What is the number of atom in a unit cell of
(i) face centered cubic structure
(ii) body centered cubic structure
6. What are F – centers ? Why are solids containing F – centers paramagnetic?
7. Account for the following :
(i) Fe3O4 is a ferromagnetic at room temperature but becomes paramagnetic at 850 K.
(ii) Zinc oxide on heating becomes yellow.
(iii) Frenkel defect does not change the density of AgCl crystal .
8. Chromium metal crystallizes in a body centered cubic lattice . The length of the unit cell edge is found to be 287 pm . Calculate the atomic radius of chromium
9. The density of Cu metal is 8.95 g cm-3. If the radius of Cu atom is 127.8 pm . Is the copper unit cell a simple cubic , a body centered or a face centered cubic structure ?
10. A cubic solid is made of two elements X and Y . Atoms Y are at corner of the cube and X at body centre . What is the formula of the compound ?
11. Calculate the distance between Na+ and Cl- ion in NaCl crystal if its density is 2.165 g cm-3 (Molar mass on NaCl = 58.5 g mol-1 )

 

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Be the first to comment - What do you think?  Posted by admin - February 21, 2013 at 1:14 pm

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CBSE Class 12 Chemistry Revision Test – Solutions

MM : 25                                             TIME : 40 MIN.
1. Two liquids A and B boil at 145oC respectively and 190oc respectively . Which of them has a higher vapour pressure at 80oc ?
2. Why is freezing point depression of 0.1 M sodium chloride solution nearly twice that of 0.1M glucose solution ?
3. Define the term molarity of the solution . State one disadvantage in using the molarity as the unit of concentration.
4. Define the term osmotic pressure . What is advantage of using osmotic pressure as compared to other colligative properties for the determination of molar masses of solutes in the solutions ?.
5. Non – ideal solutions exhibit either positive or negative deviation for Raoult’s law . What are these deviations and why are they caused ?
6. What mass of ethylene glycol (molar mass = 62g mol-1) must be added to 5.50 Kg of water to lower the freezing point of water to lower the freezing point of water from 00c to – 10 .0 0c ? [Kf for water = 1.86 K Kg mol-1 )
7. What concentration of nitrogen should be present in a glass of water at room temperature. Assume a temperature of 25oc a total pressure of 1 atmosphere and mole fraction of nitrogen in air of 0.78 (Kh for N2 = 8.42 x 10-7 M/mm Hg) .
8. The boiling point elevation of 0.30 g acetic acid in 100 g benzene is 0.0633 K . Calculate the molar mass of acetic acid from this data . What conclusion can you draw about the molecular state of the solute in the solution ? [Kb = 2.53 K Kg mol-1)
9. An antifreeze solution is prepared from 222.6 g of ethyleneglycol and 200 g of water . Calculate the molality of the solution . If density of this solution be 1.072gml-1 What will be the molarity of the solution?
10. Urea forms an ideal solution in water . Determine the vapour pressure of an aqueous solution containing 10% by mass of urea at 400c ( vapour pressure of water = 55.3 mm of Hg)
11. A 4% solution of sucrose is isotonic with 3% solution of an unknown organic substance . Calculate the molecular mass of unknown substance .

 

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CBSE Chemistry Question Bank for Class 12 – The Solid State

CBSE Chemistry Question Bank for Class 12

The solid State

Very Short Answer type Questions

  1. Why are solids rigid?
  2. Name two types in which solids are broadly classified.
  3. Give one example each for a crystalline and amorphous solid.
  4. How many atoms per unit cell are present in (i) hcp (ii) fcc (iii) bcc
  5. How many tetrahedral holes are present per unit cell in an (1)hcp structure and (2) fcc structure?
  6. What type of coordination would you expect when (1)all the tetrahedral holes in an fcc structure of  anions are occupied by cations, (2) half of the tetrahedral holes in an fcc structure of anions are occupied by cations and (3) all the octahedral holes of an fcc structure

 

Be the first to comment - What do you think?  Posted by admin - February 18, 2013 at 4:10 pm

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CBSE Class 11 Study Materials

Download the study materials prepared by the expert teachers in Chemistry for CBSE Class XI arranged chapterwise.

Download them free and prepare well for your exams.

CH 1 Some basic concepts of chemistry

CH 2 Structure of Atom

CH 3 classification of elements

CH 4 chemical bonding and molecular structure

CH 5 states of matter

CH 6 Thermodynamics

CH 7-Equilibrium

CH 8-Redox -Reaction

CH 9 Hydrogen

CH 10 S-Block

CH 11 The p block element

CH 12 Organic Chemistry

CH 13 Hydrocarbons

CH 14 Environmental Chemistry

 

Be the first to comment - What do you think?  Posted by admin - September 22, 2012 at 5:08 pm

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