Crystal Systems Overview

Questions and Answers

Match the crystal systems with their axial distances or edge lengths:

Cubic = a = b = c Tetragonal = a = b ≠ c Orthorhombic = a ≠ b ≠ c Hexagonal = a = b ≠ c

Match the crystal systems with their axial angles:

Cubic = α = β = γ = 90° Tetragonal = α = β = γ = 90° Hexagonal = α = β = 90°, γ = 120° Rhombohedral or Trigonal = α = β = γ ≠ 90°

Match the examples with their corresponding crystal systems:

Cubic = NaCl, Zinc blende, Cu Orthorhombic = Rhombic sulphur, KNO3, BaSO4 Hexagonal = Graphite, ZnO, CdS Rhombohedral or Trigonal = Calcite (CaCO3), HgS (cinnabar)

Match the possible variations of the crystal systems:

<p>Cubic = Primitive, Body-centred, Face-centred Tetragonal = Primitive, Body-centred Orthorhombic = Primitive, Body-centred, Face-centred, End-centred Hexagonal = Primitive</p> Signup and view all the answers

Match the crystal systems with their characteristics:

<p>Cubic = α = β = γ = 90° and a = b = c Tetragonal = α = β = γ = 90° and a = b ≠ c Rhombohedral or Trigonal = α = β = γ ≠ 90° and a = b = c Hexagonal = α = β = 90°, γ = 120° and a = b ≠ c</p> Signup and view all the answers

Study Notes

Crystal Systems Overview

Crystal systems classify minerals and materials based on their symmetry and geometrical arrangement.
Each system is characterized by specific axial distances and angles.

Cubic System

Variations: Primitive, Body-centred, Face-centred.
Edge lengths: All edges are equal (a = b = c).
Angles: All angles are right angles (α = β = γ = 90°).
Common examples: Sodium chloride (NaCl), Zinc blende, Copper (Cu).

Tetragonal System

Variations: Primitive, Body-centred.
Edge lengths: Two edges are equal and one is different (a = b ≠ c).
Angles: All angles are right angles (α = β = γ = 90°).
Common examples: White tin, Tin(IV) oxide (SnO2), Titanium dioxide (TiO2), Calcium sulfate (CaSO4).

Orthorhombic System

Variations: Primitive, Body-centred, Face-centred, End-centred.
Edge lengths: All edges are different (a ≠ b ≠ c).
Angles: All angles are right angles (α = β = γ = 90°).
Common examples: Rhombic sulphur, Potassium nitrate (KNO3), Barium sulfate (BaSO4).

Hexagonal System

Variations: Primitive only.
Edge lengths: Two edges are equal and one is different (a = b ≠ c).
Angles: Two angles are right angles and one angle is 120° (α = β = 90°, γ = 120°).
Common examples: Graphite, Zinc oxide (ZnO), Cadmium sulfide (CdS).

Rhombohedral or Trigonal System

Variations: Primitive only.
Edge lengths: All edges are equal (a = b = c).
Angles: All angles are equal but not right angles (α = β = γ ≠ 90°).
Common examples: Calcite (CaCO3), Cinnabar (HgS).

Description

This quiz explores various crystal systems, highlighting their variations, axial distances, and angles. It includes examples for each system, such as cubic, tetragonal, and orthorhombic. Test your knowledge on the unique properties and classifications of these crystalline structures.