--%>
Assignment Help - homework help

F-centres

If a electron is present in place of anion in a crystal lattice, then it is termed as: (a) Frenkel defect  (b) Schottky defect  (c) Interstitial defects (d) F-centre

Answer: (d) When electrons are trapped in anion vacancies, these are called F-centres.

   Related Questions in Chemistry

  • Q : Number of electrons in the benzene

    Describe the number of electrons in the benzene? Write a short note on it?

    		•
  • Q : Molality of Sulfuric acid Choose the

    Choose the right answer from following. The molality of 90% H2SO4 solution is: [density=1.8 gm/ml]  (a)1.8 (b) 48.4 (c) 9.18 (d) 94.6

    		•
  • Q : Dependcy of colligative properties

    Colligative properties of a solution depends upon: (a) Nature of both solvent and solute (b) The relative number of solute and solvent particles (c) Nature of solute only (d) Nature of solvent only

    		•
  • Q : Vapour pressure over mercury Choose the

    Choose the right answer from following. At 300 K, when a solute is added to a solvent its vapour pressure over the mercury reduces from 50 mm to 45 mm. The value of mole fraction of solute will be: (a)0.005 (b)0.010 (c)0.100 (d)0.900

    		•
  • Q : Problem on mole fraction of glucose

    Provide solution of this question. While 1.80gm glucose dissolve in 90 of H2O , the mole fraction of glucose is: (a) 0.00399 (b) 0.00199 (c) 0.0199 (d) 0.998

    		•
  • Q : Atmospheric pressure Give me answer of

    Give me answer of this question. The atmospheric pressure is sum of the: (a) Pressure of the biomolecules (b) Vapour pressure of atmospheric constituents (c) Vapour pressure of chemicals and vapour pressure of volatile (d) Pressure created on to atmospheric molecules

    		•
  • Q : Various cons of eating the organic foods

    Describe the various cons of eating the organic foods? Briefly illustrate it.

    		•
  • Q : What are homogenous catalyst? Give few

    When a catalyst mixes homogeneously with the reactants and forms a single phase, the catalyst is said to be homogeneous and this type of catalysis is called homogeneous catalysis. Some more examples of homogeneous catalysis are:    SO2

    		•
  • Q : Show your calculations Superphosphate

    Superphosphate has the formulae: CaH4 (PO4)2H2).  Calculate the percentage of phosphorus in this chemical.  Show your calculations  (around ten lines);  also Work out how to make up a nutrient mixtur

    		•
  • Q : Finding Molarity of final mixture Can

    Can someone help me in finding out the right answer. 25ml of 3.0 MHNO3 are mixed with 75ml of 4.0 MHNO3. If the volumes are adding up the molarnity of the final mixture would be: (a) 3.25M (b) 4.0M (c) 3.75M (d) 3.50M

    		•