Crystal Lattice and Unit cells

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Crystal Lattice and Unit cells: Overview

This Topic covers sub-topics such as Bravais Lattices, Crystal Lattice, Unit Cell, Tetragonal Crystal System, Hexagonal Crystal System, Rhombohedral Crystal System, Monoclinic Crystal System, Cubic Crystal System, Primitive Unit Cell and, Lattice Points

Important Questions on Crystal Lattice and Unit cells

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You are given marbles of diameter 10 mm. They are to be placed such that their centres are lying in a square bound by four lines each of length 40 mm. The number of marbles per unit area is

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The figures given below show the location of atoms in three crystallographic planes in a FCC lattice.

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The planes in the unit cell have been highlighted in the diagram below choose the correct option.

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Chromium metal crystallizes with a body centred cubic lattice. The length of the unit cell edge is found to be 287 pm. What would be the density of chromium in g/c m 3 ?

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The edge length of unit cell of a metal having molecular weight  75g/mol is  5Å which crystallizes in cubic lattice. If the density is  2g/cc  then the radius of metal atom  ( N A =6× 10 23 )  will be (in pm):

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The density of mercury is 13.6 g ml-1. The approximate diameter of an atom of mercury assuming that each atom is occupying a cube of edge length equal to the diameter of the mercury atom is

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The coordination number of a metal crystallizing in a hexagonal close-packed structure is:

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Define centred unit cell. What are the types of centred unit cells?

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Draw the schematic representation of lattice points in primitive unit cells.

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How many types of centred unit cells are there?

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_____ unit cells have points at the corners as well as at some other positions.

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The correct option for the number of body centred unit cells in all 14 types of Bravais lattice unit cells is:

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The number of lattice points in an end-centred unit cell are:

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The co-ordination number of a body-centred atom in cubic structure is:

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A substance AxBy crystallises in an f.c.c. lattice in which the atoms of 'A' occupy each corner of the cube and the atoms of 'B' occupy the centres of each face of the cube. Identify the correct composition of the substance AxBy.

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In F.C.C. the cell is shared equally by how many unit cells?

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In the Bragg's equation for diffraction of X-rays, n represents for

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Bragg's law is given by the equation :

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Correct relation between radius of atom and edge length in body centred cubic crystal is:

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Packing efficiency of body centred unit cell is:

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NaCl and KCl crystallize in a FCC structure. Their respective diffraction patterns will look like _____