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प्रश्न
The number of tetrahedral voids per unit cell in NaCl crystal is:
(i) 4
(ii) 8
(iii) twice the number of octahedral voids.
(iv) four times the number of octahedral voids.
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उत्तर
(ii) 8
(iii) twice the number of octahedral voids.
Explanation:
NaCl has fee arrangement of CF ions. Thus,
Number of CF ions in packing per unit cell = 4
Number of tetrahedral voids = 2 × No. of particles present in close packing = 2 × 4 = 8
Number of tetrahedral voids = 2 × No. of octahedral voids
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