chapter 2 (notes)

• Mass


  Amount of matter in an object
• Element


  Simplest form of matter, examples: C, H, O, N, Na, K, Ne, Cl
• Atomic Number


  The number of protons in each atom
• Mass Number


  The number of protons and neutrons in each atom
• Ionic Bond Example


  • NaCl
• Covalent Bond


  Occurs when atoms share one or more pairs of electrons
• Covalent Bond Example


  • Hydrogen molecule
• Polar Covalent Bond


  Forms when there is an unequal sharing of electrons
• Polar Covalent Bond Example


  • H2O (water)
• Polar Molecule


  Has an asymmetrical electrical charge
• Nonpolar Molecule


  Has a symmetrical electrical charge
• Hydrogen Bond


  Forms when the positive end of one polar molecule is weakly attracted to the negative end of another polar molecule
• The hydrogen bond is a weaker bond than the ionic or covalent bonds
• Molecule


  2 or more atoms chemically combine
• Molecule Example


  • Water (H2O)
• Compound


  Chemical combination of 2 or more different types of atoms
• Compound Example


  • NaCl
• Chemical Reaction


  1. Occurs when there is a formation or breaking of chemical bonds between atoms, ions, molecules, or compounds

  2. Reactants: substances that enter into the reaction

  3. Products: substances that result from the reaction
• Synthesis Reaction Example


  • ADP + P = ATP
• Decomposition Reaction Example


  • ATP ---> ADP + P
• Exchange Reaction Examples


  • AB + CD ---> AC + BD
  • HCl + NaCl ---> NaCl + H2O
• Equilibrium


  When the rate of the product formation equals the rate of reactant formation
• Energy


  The capacity to do work
• Work


  The moving of matter
• Kinetic Energy


  Energy in motion
• Potential Energy


  Stored energy
• Chemical Energy


  A form of potential energy stored in chemical bonds, food molecules such as glucose contain potential energy
• Example of Reaction that Releases Energy

  • The breakdown of ATP (adenosine triphosphate) to add ADP (adenosine diphosphate)
• Factors Influencing Rate of Chemical Reactions

  • Concentration of the reactants
  • Temperature
  • Catalyst
• Inorganic Chemistry


  Deals with substances that do not contain carbon
• Organic Chemistry


  The study of carbon-containing substances
• Some carbon-containing compounds are not organic in that they do not also contain hydrogen, such as CO2 (carbon dioxide)
• Organic Molecule


  • Carbon's ability to form covalent bonds with other atoms makes it possible the formation of large, diverse molecules
• tǒ


  Temperature
• CatalysǓ


  Concentration of the reactants
• Concentration of the reactants

  Within limits the higher the concentration of reactants the faster the rate
• Temperature


  Within limits, the higher the temperature the faster the rate
• Catalyst


  • Increases the rate of a reaction without itself being permanently changed or depleted
• Carbon's ability to form covalent bonds with other atoms


  • Makes it possible the formation of large, diverse, complicated molecules for life
• Four major groups of organic molecules essential to living organisms

  • Carbohydrates
  • Lipids
  • Proteins
  • Nucleic acids