The Solid State

  • Question 61
    CBSEENCH12005409

    For tetrahedral co-ordination, what should be the range of radius ratio (r+/r) value?

    Solution
    For tetrahedrtal coordination Radius ratio is 0.225-0.414.
    Question 62
    CBSEENCH12005410

    What type of structure possessed by a unit cell of CsCl.

    Solution
    CsCl has a body centred cubic structure.
    Question 63
    CBSEENCH12005411

    What is the effect of increasing temperature on the conductivity of semi-conductors?

    Solution
    In case of semiconductors, the gap between the valence band and conduction band is small  Therefore, some electrons may jump to conduction band and show some conductivity. Electrical conductivity of semiconductors increases with rise in temperature, since more electrons can jump to the conduction band.
    Question 64
    CBSEENCH12005412

    Define radius ratio. What is the ideal value for a tetrahedral void?

    Solution
    It is the ratio of the radius of the cation to the radius of the anion in an ionic crystal.the radius ratio of tetahedral is in between 0.225-0.732. Its ideal value is 0.225 for tetrahedral void.

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