States of Matter

States of Matter

• Four main states of matter: solid, liquid, gas, and plasma
• States of matter can be changed by altering temperature and pressure
• Characteristics of each state:
  • Solid:
    • Fixed shape and volume
    • Particles closely packed and vibrate in place
  • Liquid:
    • Takes shape of container
    • Particles close together but can move past each other
  • Gas:
    • Takes shape and volume of container
    • Particles widely spaced and move freely
  • Plasma:
    • High-energy state where atoms are ionized
    • Particles highly energetic and move freely

Physical Properties

• Physical properties of matter that can be observed and measured:
  • Extensive properties:
    • Depend on amount of matter (e.g., mass, volume)
  • Intensive properties:
    • Independent of amount of matter (e.g., density, temperature)
• Examples of physical properties:
  • Color
  • Odor
  • Texture
  • Melting point
  • Boiling point
  • Solubility

Particles

• Matter is composed of tiny particles called atoms and molecules
• Atoms:
  • Smallest unit of matter
  • Consist of protons, neutrons, and electrons
• Molecules:
  • Group of atoms bonded together
  • Can be composed of same or different elements
• Particle motion:
  • Kinetic molecular theory: particles in constant motion
  • Temperature affects particle motion (increased temperature = increased motion)

Density

• Density: mass per unit volume of a substance
• Calculated by: density = mass / volume
• Units: typically g/cm³ or kg/m³
• Density is an intensive property, meaning it is independent of amount of matter
• Examples of density values:
  • Water: 1 g/cm³
  • Iron: 7.9 g/cm³
  • Air: approximately 1.2 kg/m³

States of Matter

• Four main states of matter: solid, liquid, gas, and plasma, which can be changed by altering temperature and pressure.
• Solids have a fixed shape and volume, with particles closely packed and vibrating in place.
• Liquids take the shape of their container, with particles close together but able to move past each other.
• Gases take the shape and volume of their container, with particles widely spaced and moving freely.
• Plasma is a high-energy state where atoms are ionized, with particles highly energetic and moving freely.

Physical Properties

• Physical properties of matter can be observed and measured, and are classified as extensive or intensive.
• Extensive properties depend on the amount of matter, such as mass and volume.
• Intensive properties are independent of the amount of matter, such as density, temperature, color, odor, texture, melting point, boiling point, and solubility.

Particles

• Matter is composed of tiny particles called atoms and molecules.
• Atoms are the smallest unit of matter, consisting of protons, neutrons, and electrons.
• Molecules are groups of atoms bonded together, which can be composed of the same or different elements.
• Particle motion is constant, and temperature affects particle motion, with increased temperature resulting in increased motion.

Density

• Density is the mass per unit volume of a substance, calculated by dividing mass by volume.
• Density is an intensive property, independent of the amount of matter.
• Units of density are typically g/cm³ or kg/m³.
• Examples of density values include water (1 g/cm³), iron (7.9 g/cm³), and air (approximately 1.2 kg/m³).