Important Vocabulary/Chapter Summary

• Properties of Solids

• Properties of Liquids

• Properties of Gases

• Pressure, Temperature, and Kinetic Energy

Particulate Characteristics of Solids

• The motion of individual particles is limited.

  • Particles do not undergo translation with respect to one another.

• Particles are very close together.

• The structures are held by intermolecular forces and/or chemical bonds.

• Structure is influenced by the ability of the particles to pack together.

Amorphous Solids

• Random arrangement of particles.

• Particles have no orderly structure.

• Macroscopic structures lack well defined faces and shapes.

• Many are mixtures of molecules that do not stack up well together.

• Glass and rubber are examples of amorphous solids.

Crystalline Solids

• Atoms, ions, or molecules are arranged in an orderly fashion that allows a pattern of repetition in three dimensions.

  • The segments that are repeated in three dimensions are called unit cells.

• macroscopic structures usually have flat surfaces that make definite angles to one another.

• Quartz and ionic Solids are crystalline.

Amorphous & Crystalline Solids

• Glass is amorphous

• Quartz is crystalline

Properties of Liquids

• Particles are constantly moving and colliding with one another.

  • particles undergo translation with respect to one another.

  • movement is influence by the strength of the intermolecular forces that are present between the particles and the temperature.

• Particles are very close together

Volume of Solid & Liquid Phases

• The solid and liquid phases for a particular substance normally have similar molar volumes.

• The density of particles is similar in both phases.

• Ice has a slightly larger molar volume than liquid water.

• Most solids have a slightly smaller molar volume than their liquids.

Pressure

pressure (pa) = Force (N) / Area (m²)

• Gases exert pressure by bonding off surfaces

• Gas particles are evenly distributed in a container.

• The same number smash off every cm² per unit of time.

  • Each collision exerts a force.

• The pressure is constant at constant temperatures.

• Gas exerts pressure in all directions.

• Conversions:

  • 1 atm =

    • = 760mm Hg

    • = 760 torr

    • 101,325 Pa

Boyles Law

• The relationship between Pressure and Volume of gases

• V1P1 = V2P2

  • V = Volume

  • P = Pressure

• Volume is inversely proportional to pressure.

Pressure - Volume Relationship

• Always use K instead of Celsius

  • K = Celsius (C) + 273.15

Temperature

• A measure of the average kinetic energy of atoms and molecules in a system.

  • The Kelvin (K) temperature scale is proportional to this.

  • When KE doubles, the kelvin temperature doubles.

Kinetic ENergy of Gas Molecules

• Translational Energy

  • Gas molecules move through space in straight lines

• Rotational Energy

• Vibrational Energy

Charles’ Law

• The relationship between temperature and volumes of gases.

  • V1/T1 = V2/T2

• Volume is Proportional to temperature

• You MUST use absolute temperature.

Temperature - Volume Relationship

• Higher temperature, higher volume

• Lower temperature, lower volume

Properties of Gases

• The Motion of individual particles is limited.

  • Particles do not undergo translation with respect to one another.

• Particles are very close together

• The structures are held together by intermolecular forces and/or chemical bonds

• Particles are constantly moving

• they expand to fill the volume of the container they occupy

• from homogenous mixtures

• Low density

• Highly compressible

• Exerts a pressure

• Does not have a definite shape or a definite volume, as they are constantly moving and, ideally, there is no force of attraction between particles.

• Collision frequency and density of gas particles depends on pressure, volume, and temperature.