SCIENCE 10-Q4: Kinetic Molecular Theory, Boyle's Law, & Charles' Law

• Kinetic Molecular Theory


  The tiny particles in all forms of matter are in constant motion
• Kinetic


  Refers to motion
• Kinetic Molecular Theory


  • Helps you understand the behavior of solid, liquid, and gas atoms/molecules as well as the physical properties
  • Provides a model behavior based on three principals
• 3 Principles of Kinetic Molecular Theory

  • All matter is made of tiny particles (atoms)
  • These particles are in constant motion
  • When particles collide with each other or the container, the collisions are perfectly elastic (no energy is lost)
• 5 States of Matter

  • Bose-Einstein Condensates
  • Solid
  • Liquid
  • Gas
  • Plasma

  
• Phase


  Each of the different states of matter (solids, liquids, gases, plasmas, and Bose-Einstein condensates) is also known as a phase

  
• Elements and compounds can move from one phase to another phase when special physical forces are present
• Temperature


  One example of the physical forces that can cause phase changes
• Bose-Einstein Condensate


  • Particles are extremely close together
  • Particles barely move
  • Only found at extremely cold temperatures
  • Basically Bose-Einstein is a cold solid
  • Lowest energy of the 5 states/phases of matter
• Solids


  • Particles are tightly packed and close together
  • Particles do move but not very much
  • Definite shape and definite volume (because particles are packed closely and do not move)
  • Most solids are crystals
  • Crystals are made of unit cells (repeating patterns)
  • The shape of a crystal reflects the arrangement of the particles within the solid
• Allotropes


  Solids that appear in more than one form, with 2 or more different molecular forms of the same element in the same physical state (have different properties)
• Allotropes of Carbon


  • Powder = Graphite
  • Pencil "lead" = graphite
  • Hard solid = diamond
• Amorphous Solids


  • A solid with no defined shape (not a crystal)
  • A solid that lacks an ordered internal structure
• Liquids


  • Particles are spread apart
  • Particles move slowly through a container
  • No definite shape but do have a definite volume
  • Flow from one container to another
• Viscosity


  Resistance of a liquid to flowing
• Viscosity


  • Honey - high viscosity
  • Water - low viscosity
• Gases


  • Particles are very far apart
  • Particles move very fast
  • No definite shape and No definite volume
• Plasma


  • Particles are extremely far apart
  • Particles move extremely fast
  • Only exists above 3000 degrees Celsius
  • Basically, plasma is a hot gas
  • When particles collide, they break apart into protons, neutrons, and electrons
  • Occurs naturally on the sun and stars
• Phase Change


  During a phase change, heat energy is either absorbed or released
• Melting


  • Phase change from a solid to a liquid
  • Molecules speed up, move farther apart, and absorb heat energy
  • Melting point - 0° Celsius (the temperature at which a solid changes to a liquid)
• Freezing


  • Phase change from a liquid to a solid
  • Molecules slow down, move closer together and release heat energy
  • Freezing point - 0° Celsius
• Vaporization (Boiling)


  • Phase change from a liquid to gas
  • It occurs at the boiling point of matter
  • Molecules speed up, move farther apart, and absorb heat energy
  • Boiling point - 100° Celsius
• Evaporation


  • Phase change from a liquid to a gas on the surface of a liquid (occurs at all temperatures)
  • Molecules speed up, move farther apart, and absorb heat energy

  
• Condensation


  • Phase change from a gas to a liquid
  • Molecules slow down, move closer together and release heat energy
• Liquid-Gas Phase Changes


  • Vaporization: the change of a substance from a liquid to a gas
  • Evaporation: if vaporization takes place at the surface of the liquid
  • Condensation: if a substance in the gas phase loses heat energy, it changes into a liquid
• Liquid-Gas Phase Changes


  • A cold glass iced drink tends to become wet on the outside (water vapor condenses)
  • Rain
• Deposition


  • Phase change from a gas to a solid
  • Molecules slow down, move closer together and release heat energy
  • When water vapor in air loses so much energy it turns directly into a solid
• Properties that Describe a Gas

  • Pressure (P)
  • Volume (V)
  • Temperature (T)
  • Amount (n)
• Gas Pressure (P)


  • Force acting on a specific area
  • Units: atm, mmHg, torr, lb/in^2, Kilopascals (KPa)
  • Container: sealed, constant pressure.
• Gas Volume (V)


  • 3-Dimensional space occupied by a gas
  • Units: mL, L, m^3, cm^3
  • 1L = 100ml, 1ml = 1cm^3
• Gas Temperature (T)


  • Measure of the warmth/coldness of a body
  • Measure of the average kinetic energy of the particles in an object
  • Units: Fahrenheit (°F), Celsius (°C), Kelvin (K)
  • Answers/Solutions must be in KELVIN
• Gas Quantity (n)


  • Measured in moles (mol)
  • 1 mole = 6.022 x 10^23 units of substance
• Boyle's Law


  • Pressure is inversely proportional to the volume at constant temperature
  • When volume increases, pressure decreases. When volume decreases, pressure increases.
• Applications of Boyle's Law

  • Action of a Syringe
  • Bringing a bag of chips
  • Breathing
• Charles's Law


  • Volume is directly proportional to the temperature at constant pressure
  • A gas expands when its temperature increases. It contracts when temperature decreases.
• Applications of Charles's Law

  • Hot Air Balloons
  • Ping-Pong Balls
  • Baking
• Robert Boyle


  The physicist that formulated the Boyle's Law.
• Jacques Charles


  The scientist who discovered the "Charles' Law"