Properties and Types of Solids – Vocabulary Review

Vocabulary flashcards covering fundamental terms and definitions from the lecture on properties and types of solids, including structural concepts, mechanical traits, and classifications of crystalline materials.

Solid State

Phase of matter with definite shape and volume, particles in fixed positions, strong intermolecular forces, and low kinetic energy.

Physical Property

A characteristic of matter (e.g., color, density, texture) observable without changing the substance’s identity.

Chemical Property

A characteristic that can only be observed when a substance transforms into a different substance.

Physical Change

A change in size, shape, or phase where the substance’s identity remains the same.

Chemical Change

A transformation that converts one substance into a different substance.

Density

Mass per unit volume of a material; independent of a sample’s quantity or shape.

Displacement Method

Technique for finding an object’s volume by measuring the amount of fluid it displaces.

Malleability

Ability of a solid to be pounded or rolled into thin sheets without breaking.

Ductility

Ability of a material to be bent or drawn into wires without breaking.

Crystalline Solid

Solid in which particles form a long-range, repeating 3-D pattern called a crystal lattice.

Amorphous Solid

Solid lacking long-range order; particles are randomly arranged, often formed by rapid cooling (e.g., glass).

Crystal Lattice

The ordered, three-dimensional arrangement of points representing particle positions in a crystalline solid.

Space Lattice

Diagram showing how constituent particles are arranged at different positions in three-dimensional space.

Unit Cell

Smallest repeating boxlike unit that builds up a crystal lattice in three dimensions.

Bravais Lattices

The 14 basic three-dimensional lattice types possible for crystal structures.

Seven Crystal Systems

Seven basic geometric categories (cubic, tetragonal, etc.) used to classify unit-cell shapes.

Molecular Solid

Crystalline solid whose lattice points are neutral molecules held by weak intermolecular forces.

Nonpolar Molecular Solid

Molecular solid held mainly by London dispersion forces; usually soft with very low melting points (e.g., solid CO₂).

Polar Molecular Solid

Molecular solid stabilized by dipole-dipole interactions; melts more easily than ionic or metallic solids (e.g., SO₂).

Hydrogen-Bonded Molecular Solid

Molecular solid where molecules are linked by hydrogen bonds, giving higher melting points (e.g., ice).

Van der Waals Forces

Weak attractions—including London dispersion and dipole-dipole forces—between molecules in molecular solids.

London Dispersion Forces

Weakest intermolecular forces arising from temporary induced dipoles in nonpolar molecules.

Dipole-Dipole Interaction

Attraction between permanent dipoles of polar molecules.

Supercooled Liquid

Term often applied to amorphous solids because their random arrangement resembles a rapidly cooled liquid state.

Metallic Solid

Solid consisting of positive atomic cores immersed in a ‘sea’ of delocalized electrons.

Metallic Bond

Electrostatic attraction between positive metal ions and surrounding delocalized electrons.

Ionic Solid

Solid composed of cations and anions held together by Coulombic (electrostatic) attractions.

Coordination Number

Number of oppositely charged ions surrounding a given ion in an ionic crystal lattice.

Covalent Network Solid

Solid in which atoms are linked in a continuous network by covalent bonds (e.g., diamond, SiC).