Physical and Chemical Properties of Matter

Matter and Its Properties

Introduction

  • Matter is composed of particles and empty space.
  • Matter can be described through its unique properties.
  • Two main categories for describing matter:
    • Physical properties
    • Chemical properties

Physical Properties

  • Define physical characteristics of a substance, not chemical behavior.
  • Examples:
    • Malleability: Ability of a metal to be hammered into thin sheets (e.g., aluminum foil).
    • Ductility: Ability of a metal to be drawn into wires (e.g., copper).
    • Boiling Point: Temperature at which a liquid turns into vapor (e.g., water's boiling point is 100∘C100^{\circ}C).
    • Frequency: Amount of wavelengths that pass a given point every second (e.g., wave frequency of 2020 Hz).
    • Viscosity: Resistance of a fluid to flow (e.g., honey is more viscous than water).
    • Solubility: Ability of a substance to dissolve in a solvent (e.g., salt and sugar are soluble in water).

Chemical Properties

  • Describe how a substance's chemical composition will change under specific conditions.
  • Examples:
    • Flammability: Ability to burn when exposed to a flame (e.g., gasoline is flammable).
    • Radioactivity: Tendency of an atom's nucleus to change over time.
    • Corrosiveness: Ability to corrode or damage other substances (e.g., battery acid is corrosive).
    • Oxidizer: Ability to strip electrons from another substance.
    • Combustibility: Ability to react with an open flame (e.g., oxygen is combustible and becomes carbon dioxide and water vapor).
    • Toxicity: Ability to be poisonous.
    • Explosiveness: Ability to explode (e.g. TNT is explosive).
    • Pyrophoricity: Ability to ignite spontaneously when exposed to air.

Physical vs. Chemical Properties Examples

  • Freezing Point: Physical property
  • Combustibility: Chemical property (e.g., oxygen changing to carbon dioxide and water vapor)
  • Water Reactivity: Chemical property (e.g., sodium metal reacting violently with water)
  • Viscosity: Physical property
  • Toxicity: Chemical property
  • Condensation Point: Physical property (e.g., water vapor condensing at 100∘C100^{\circ}C)
  • Pyrophoricity: Chemical property - ignites in air
  • Corrosiveness: Chemical property - like battery acid
  • Melting Point: Physical property. For example, the melting point of ice is 00 degrees Celsius.

Chemical Reactions and Properties

  • Chemical property: the ability of a substance to react with another substance to form new substances.
  • A chemical reaction produces one or more new substances.
  • Chemical properties are exhibited during a chemical reaction and change the substance; the substances after the reaction will not be the same as they were before the reaction.
  • Example: Burning paper reacts with oxygen, resulting in dust, smoke, and ash.
  • Two types of chemical properties:
    • Reactivity with water, oxygen, or acid
    • Combustibility (burning)
  • Electrolysis: chemical reaction of decomposition where a compound breaks into simpler substances.
Decomposition
  • Decomposition involves the breakdown of a compound into simpler substances.
  • Example of electrolysis: Water containing sulfuric acid broken down into hydrogen and oxygen using electrical energy.

Physical Properties (Observed/Measured)

  • Characteristics observed or measured without changing the substance's identity.
  • Noting physical property doesn't alter the substance.
  • Two types:
    • Qualitative
    • Quantitative
Qualitative Physical Properties
  • Observed and described without detailed measurement.
  • Examples:
    • Brittleness
    • Transparency
    • Color
    • Odor
    • State of matter
    • Taste
    • Texture
    • Luster (shininess)
    • Malleability
    • Ductility
Quantitative Physical Properties
  • Require measurement.
  • Examples:
    • Melting point
    • Boiling point
    • Density
    • Solubility
    • Viscosity
    • Hardness
    • Conductivity