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Extremely pure samples of Ge and Si are ...

Extremely pure samples of `Ge` and `Si` are non`-`conductors, but their conductivity increases suddenly on introducting `…………………….` in their crystal lattice

A

As

B

B

C

Both (1) and (2)

D

None of these

Text Solution

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The correct Answer is:
C
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VMC MODULES ENGLISH-THE SOLID STATE-EFFICIENT
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  2. F-centre defect is noticed in:

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  3. Extremely pure samples of Ge and Si are non-conductors, but their cond...

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  4. The resistance of Nb(3)Ge becomes almost zero at:

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  5. Statement-1: High thermal conductivity of metals is due to presence of...

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  6. Which of these is pyroelectric?

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  7. The substance which possesses zero resistance at 105 K:

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  8. The strcture of MgO is similar to NaCl. What is the co- ordination ...

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  9. An element (atomic mass = 100 g//mol) having bcc structure has unit ce...

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  10. Which of the following has the highest lattice energy ?

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  11. An element with molecular weight 200 gm/mole crystallizes in a s...

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  12. CsCl has bc c arrangement and its unit cell edge length is 400 pm. Cal...

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  13. In the face centered cubic unit cell, the radius of atoms in terms of ...

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  14. The number of atoms present in a hexagonal close-packed unit cell is:

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  15. In a solid between A and B atoms of A are arranged in ccp array and at...

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  16. The arrangement ofCI^(-) ions in CsCI structure is

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  17. Which of the following solids is the structure of CsCl crystal ?

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  18. Close packing is maximum in the crystal which is

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  19. The radius of Ag^(+) ion is 126 pm and that of I^(-)ion is 216 pm. The...

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  20. In hexagonal primitive unit cell, the Corner is shared by:

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