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States of Matter -

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States of Matter
A Matter of Kinetic Energy
Types of States of Matter
SolidLiquidGasPlasmaBEC, or Bose-Einstein CondensateZero State of MatterMost Dense
Changes of State
Kinetic Energy (kelvins&paschals)
Supercritical fluids are useful in science todayextraction of floral fragrancethe process of creating decaffeinated coffeefood science and functional food ingredientspharmaceuticals, cosmetics, polymers, powders, bio- and functional materialsnano-systems, natural products, biotechnology, fossil &biofuels, microelectronics & environment (Bottini133).
Superheated VaporWhen the temperature is higher than the boiling point @ a given pressure.Vapor cannot exist in contact with the fluid, nor contain fluid particles.Increase in pressure or decrease in temperature will not, within limits, condensate out liquid particles in the vapor.Highly superheated vapors are gases that approximately follow the general gas law.
Critical Temp & Pressure
Critical TemperatureThe temperature at which only gas exists, regardless of its pressureCritical PressureThe lowest pressure at which liquids exist at critical temperatureCritical PointThe intersection of critical temperature & pressure
CO2Phase Diagram
Kinetic-Molecular Theory of Gases
Ideal gas = hypothetical gas perfectly aligns with all kinetic-molecular theory assumptionsFive AssumptionsDistance between molecules dwarfs actual sizeAll collisions are perfectly elasticParticles are in continuous, rapid, random motionParticles have NO attraction to each otherTemperature = average kinetic energy of particles
Nature of Gases
Idealvs.RealReal approaches ideal @ low pressure/ high tempExpansion – molecules fill entire spaceFluidity – no intermolecular attractionsDensity - ~ 10-3of liquid or solid stateCompressibility – 100X morethan liquidsDiffusion & EffusionDiffusion: Spontaneousmixing via random motionEffusion: Passingthrough tiny opening
Properties of Liquids
LEAST common state of matter in universeFluids (as are gases)Lower kinetic energy than gasesInteractive forces keep molecules connectedDipole-dipole forcesEqual but opposite charges separated by short distanceLondon dispersion forcesSpontaneous creation of dipoles (polar&nonpolar)Hydrogen bonding (electronegativity)
Properties of Liquids,continued
Density: 100x > gases; 10% < solidsCompressibility: @ 103atm., volume ~ 4%Diffusion: present, but slower than in gasesSurface tension: high intermolecular attractionCapillary action: attraction between surfaces of liquid and a solidVaporization: evaporation & boiling gas
Nature of Solids
Interparticle attractions stronger than othersTwo types of solidsCrystalline (orderly arrangement)Amorphous (random arrangement)supercooled liquids: have liquid properties even if looksolid (like glass and plastics)Shape & Volume: DefiniteMelting Point: DefiniteDensity & Incompressibility: HighDiffusion: Low rate (10-6less than others)
Crystalline Solids
IonicAlkali & alkaline earth with halogens & Group 16Hard, brittle, high melting points, good insulatorsCovalent networkCx(diamonds), (SiO2)xquartz, (SiC)xVery hard and brittle, high MP, semi- or nonconductorsCovalent molecular (nonpolar & polar)H2, CH4, C6H6: only weak London dispersion forcesH2O & NH3,: stronger forces but weaker than covalentSoft, low MP, low BP,good insulators





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States of Matter -