RJAV - GenChem

• Matter


  Mass + Volume
• States of Matter

  • Solid
  • Liquid
  • Gas
  • Plasma/Ionized Gas
• Solid

  Shape: Definite (non-compressible)

  Volume: Definite (non-compressible)
• Liquid


  Shape: Indefinite (assumes container shape)

  Volume: Definite
• Gas


  Shape: Indefinite (compressible)

  Volume: Indefinite (compressible)
• Molecular Motion

  Solid: Vibration

  Liquid: Gliding

  Gas: Constant random
• Plasma/Ionized Gas

  • 4th state of matter
  • most abundant state
  • has protons and electrons (thus, greatly affected by magnetic field)
• Examples of Plasma

  • Ionized Ne light
  • Aurora
  • Stars
  • Sun
• IFA (Intermolecular Forces of Attraction) Strength


  S > L > G > P
• Enthalpy (heat/reaction energy)


  P > G > L > S
• Phase Changes

  • Melting
  • Freezing
  • Evaporation
  • Condensation
  • Sublimation
  • Deposition
  • Recombination (deionization)
  • Ionization
• Melting


  Solid to Liquid

  • Fusion
  • Liquefaction
  • Thawing
• Freezing


  Liquid to Solid
• Evaporation


  Liquid to Gas
• Condensation


  Gas to Liquid
• Sublimation


  Solid to Gas
• Deposition


  Gas to Solid
• Recombination


  Plasma to Gas
• Ionization


  Gas to Plasma
• Matter Classification

  • Pure substance
  • Mixture
• Pure substance

  • Element: simplest form of substance
  • Compound: 2 or more chemical united (separated via chemical means)
• Mixture


  2 or more substance wherein individual substance identifies are retained (separated via physical means)

  • Homogenous: 1 phase, clear colored solution
  • Heterogenous: 2 phases, suspension, colloid (ex. milk)
• Classification based on the amount of matter present

  • Extrinsic property: Dependent
  • Intrinsic property: Independent
• Examples of Extrinsic property

  • Length
  • Mass/Weight
  • Volume
  • Pressure
  • Entropy
  • Enthalpy
  • Electrical resistance
• Examples of Intrinsic property

  • Density/SpGr
  • Viscosity
  • Velocity
  • Temperature
  • Color
• Law of Conservation of Mass/Matter - Antoine Lavoiser


  Mass/Matter is always constant (neither created nor destroyed)
• Law of Definite/Constant Proportions - Joseph Proust


  Proust's Law: Chemical compounds always contain the exact proportion of element in fixed ratio (by mass)
• Law of Multiple Proportion - John Dalton


  When 2 elements form more than 1 compound, it can be expressed in a fixed whole number (by mass)
• Law of combining weights


  Proportions by weight when chemical reaction takes place can be expressed in small integral unit
• Democritus


  Atomos = Indivisible
• John Dalton - Billiard ball


  Postulates:

  • Matter is made up of atoms
  • Elements are composed of indivisible and indestructible atoms
  • Atoms alike for a given element (isotopes)
  • Atoms of different elements differ in size, mass & other properties (isobars)
  • Compound are formed form 2 or more atoms at different elements
  • Atoms combined in simple numerical ratios to form compounds
• Joseph John Thomson / JJ Thomson - Plum Pudding / Raisin Bread Model


  discovered electrons in (+) framework
• Ernest Rutherford - Nuclear (Gold foil / alpha-scattering experiment)


  discoverer of protons

  • atom is mostly empty; (+) particles in nucleus
• Neils Bohr - Planetary Model


  mostly used model

  • electrons moved around the nucleus
• Erwin Schrodinger - Quantum / Mechanical / e- cloud


  Modern Atomic Model: estimates the probability of finding an e- in certain position
• Proton = Atomic number
• Electron = Protons in uncharged state


  negligible weight 1836x lighter than protons
• JJ Thomson - Cathode ray tube


  e- m/2 ratio
• RA Millikan - Oil Drop Experiment 


  measures accurate charge and mass of e-
• Neutrons = Atomic Mass - Protons/Atomic Number


  no charge

  James Chadwick: discoverer of neutrons