Close Packed Structures And Packing Efficiency

IMPORTANT

Close Packed Structures And Packing Efficiency: Overview

This topic covers concepts such as Coordination Number, Packing Fraction of an Unit Cell, Close Packing of Spheres in Crystalline Solids, Close Packing of Lattice Points in One Dimension, Close Packing of Lattice Points in Two Dimension, etc.

Important Questions on Close Packed Structures And Packing Efficiency

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Silver crystallises with face-centred cubic unit cells and each side of the unit cell has a length of 409 pm. Determine the radius of an atom of silver. (Assume that each face atom is touching the four corner atoms.)

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A metallic element crystallises into lattice having a layering sequence of ABABAB. Any packing of sphere leaves out voids in the lattice. Determine what percentage by volume of this lattice is empty space.

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Sodium metal crystallises in a body centred cubic lattice with the cell edge,  a=4.29Å. What is the radius of a sodium atom?

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CsBr has bcc structure with edge length 4.3 Å . The shortest inter ionic distance in between Cs+ and Br is:

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In curing cement plasters water is sprinkled from time to time. This helps in

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What is the radius of sodium atom if it crystallizes in bcc structure with the cell edge of 400 pm ?

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Column I (Type of crystal) Column II (Location of cations/anions) 
(A) NaCl  (p) Cations-fcc, Anions-all tetrahedral voids 
(B) ZnS (q) Anions-fcc, Cations-all tetrahedral voids
(C) CaF2 (r) Anions-fcc, Cations-all octahedral voids
(D) Na2O (s) Anions-fcc, Cations-alternate tetrahedral voids

 

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In a simple cubic lattice, the co-ordination number is :

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The lattice generated in three-dimensional closed packing from two-dimensional square close-packed layers is

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Explain three-dimensional close packing from two-dimensional square close packed layers.

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The relationship between edge length and the radius of the simple cubic unit cell is _____.

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What is coordination number? Give the coordination number of the simple cubic lattice.

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The coordination number for molybdenum in hexagonal closed packing is 

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The coordination number in one-dimension close packing is 

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The coordination number is equal to _____ in one-dimensional close packing in crystalline solid.

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Describe close packing in one dimension in crystalline solids.

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The lattice generated in three-dimensional closed packing from two-dimensional square close-packed layers is

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Define three-dimensional close packing from two-dimensional square close-packed layers.

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Two dimensions coordination number of a molecule in square close-packed layers is

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Discuss the alignment of spheres in the square closed packing in two dimensions.