NEW
Font size
WorksheetsCrystal Structure
Total questions: 21
Worksheet time: 11mins
long-range order exists
Crystalline material
Amorphous Material
long-range atomic order is absent
Crystalline material
Amorphous Material
Spheres representing nearest-neighbor atoms touch one another.
Atomic hard-sphere model
Bohr Model
Reduced sphere model
Lattice
means a three-dimensional array of points coinciding with atom positions
Lattice
Amorphous
Unit Cells
FCC
the basic structural unit or building block of the crystal structure and defines the crystal structure by virtue of its geometry and the atom positions within
Lattice
Amorphous
Unit Cells
FCC
Cube edge length a or x and the atomic radius R in FCC is related by
a = 2R√𝟐
a = 34R
In order to compute the number of atoms per unit cell for the HCP crystal structure we will use
N=Ni +2Nf+8Nc
the sum of the sphere volumes of all atoms within a unit cell (assuming the atomic hard-sphere model) divided by the unit cell volume
Atomic packing factor (APF)
Total unit cell volume
Volume of atoms in a unit cell
when metals and nonmetals have more than one crystal structure
Polymorphism
Allotropy
Allotropy is
when more than one crystal structure is found in elemental solids
when metals and nonmetals have more than one crystal structure
There are nine different possible combinations of which represents a distinct crystal system.
True
False
Crystallography
science of measuring the crystal structure of a crystal
science of combining crystals with another crystals
science of determining the color of a crystal
science of measuring the reactants of a crystal
defined as a line directed between two points, or a vector
crystallographic direction
crystallographic position
crystallographic color
crystallographic size
Which has a
a=b=c Axial relationship?Orthorhombic
Rhombohedral
Tetragonal
Cubic
Which has an Interaxial Angles of
α=γ=90°=β ?Monoclinic
Triclinic
Hexagonal
None of this
Which has an Interaxial Angles of
α=β=90°,γ=120° ?Monoclinic
Triclinic
Hexagonal
None of this
Which has an Interaxial Angles of
α=β=γ=90° ?Rhombohedral
Triclinic
Hexagonal
Cubic
defined as the number of atoms per unit length whose centers lie on the direction vector for a specific crystallographic direction
Linear Density (LD)
Atomic Density (AD)
Unit Cell Density (UCD)
Planar Density (PD)
taken as the number of atoms per unit area that are centered on a particular crystallographic plane
Linear Density (LD)
Atomic Density (AD)
Unit Cell Density (UCD)
Planar Density (PD)
the result when the periodic and repeated arrangement of atoms is perfect or extends throughout the entirety of the specimen without interruption
single crystal
polycrystalline
grain boundary is
an area where some atomic mismatch within the region
where two grains meet
when the periodic and repeated arrangement of atoms is perfect or extends throughout the entirety of the specimen without interruption
number of atoms centered on a plane
crystals having hexagonal symmetry
