CHEMISTRY (CETS)

• Chemistry


  the science of properties, composition, and structures of matter, the changes it undergoes, and the laws and principles which govern these changes.
• Branches of Chemistry


  1 Organic Chemistry

  2 Inorganic Chemistry

  3 Analytical Chemistry

  4 Physical Chemistry

  5 Biochemistry
• Organic Chemistry


  study of chemicals containing carbon
• Inorganic Chemistry


  all elements and compounds other than organic compounds

  • does not have carbon
• Analytical Chemistry


  study of qualitative and quantitative analysis of element sand compounds
• Physical Chemistry


  stuyd of reaction rates, mechanisms, bonding and structure, and thermodynamics
• Biochemistry


  the study of the chemical reactions that happen within the biological process
• Matter


  anything that occupies space and has mass
• Volume


  amount of space it occupies
• Mass


  amount of matter it contains
• Physical Properties of Matter

  do not change as it is being observed

  • Intrinsic and Extrinsic
• Intrinsic

  distinguish substance from another substance

  • do not depend on the amount of matter present
  • acidity, boiling point, hardness
• Extrinsic


  depend on the amount of matter present

  • temperature, volume, shape,
• Mass and Energy Relation

  developed by Albert Einstein

  • increase in mass increases energy and vice versa
  • any object with mass has an inherent amount of energy called "rest energy"
• e = mc^2


  Formula for Mass and Energy Relation
• Total Energy (e)


  rest energy (mc^2) + kinetic energy (1/2ms^2)
• Physical Change


  only the physical properties of a substance is changed
• Chemical Change


  identity of the substance is altered
• Law of Conservation of Mass

  developed by Antoine Lavoiser

  • mass cannot be created or destroyed in a closed system through ordinary chemical or physical reactions
  • total mass of the reactants = total mass of the producers
• Evidences of a Chemical Change

  1 Evolution of Heat and Light

  2 Evolution of a Gas

  3 Formation of a Precipitate

  4 Production of Mechanical Energy

  6 Production of Electrical Energy
• Law of Definite Composition/Proportion


  elements combine in ratios of simple whole numbers to form a compound

  • every sample of a given substance always contain the same proportion by mass of its constituent elements
• Law of Multiple Proportions


  in compounds, if one element is constant, other elements in different compound are in ratio of a small whole number
• Isomer


  different compounds containing same elements
• Energy in Chemical Reaction

  during chemical reactions, energy is either released or absorbed
• Endothermic


  energy is absorbed/taken in
• Exothermic


  energy is released
• Reaction Activism


  series of chemical steps involved in a chemical reaction
• Activation ENergy


  minimum amount of energy is needed to initiate a chemical reaction
• Heat of Reaction


  total amount of heat released/absorbed
• KJ/mol


  how heat of reaction is measured
• △H


  used to symbolize heat of reaction
• negative △H


  for exothermic
• positive △H 


  for endothermic
• Le Chatlier's Principle


  developed by Henri Louis de Chatlier

  • Change in Concentration
  • Change in Temperature
  • Change in Pressure/Volume
• Pure Substance


  either element or compound

  • element always present in the same ratio in given compound
• Element


  simplest form of substance that cannot be decomposed anymore
• Metals


  hard and shiny elements that are good conductors of heat and electricity

  • often lose electrons
• Nonmetals


  brittle elements that do not conduct heat or electricity very well
• Metalloids 


  borderline elements between metals and nonmetals
• Compound


  substance formed with 2 or more elements combined chemically