Chapter 2 Animations    Art 

Unit 1: The Chemistry of Life The Chemical Context of Life Review
  1. Living organisms are subject to basic laws of physics and . One example is the use of formic acid by ants to maintain "devil’s gardens".
     
     
     
     
  2. Matter consists of chemical in pure form and in combinations called .
     
     
     
     
  3. Four elements make up 96% of living matter: (C), (H), (O), and (N).
     
     
     
     
  4. Each element is made of a single kind of . An atom is made of , , and .
     
     
     
     
  5. Electrons occupy different with different energy . The outermost, or , shell contains electrons.
     
     
     
     
  6. A bond is the of a pair of electrons between different atoms of a . These bonds are strong and stable.
     
     
     
     
  7. A covalent bond is the sharing of two pairs of valence electrons.
     
     
     
     
  8. Electronegativity is the attraction of an atom for . In a covalent bond the atoms have different electronegativities and share the electrons .
     
     
     
     
  9. In an bond one atom strips away from other atoms, creating atoms called .
     
     
     
     
  10. Ionic compounds are often called , which may form .
     
     
     
     
  11. Electronegativity can result in weak chemical bonds.
       
       
       
       
    • A bond forms from the attraction of charged regions of molecules.
       
       
       
       
    • interactions form when transiently charged regions of molecules attract each other.
Chapter 3 Animations    Art 

Unit 1: The Chemistry of Life Water and the Fitness of the Environment Review
  1. is the biological medium here on Earth.
     
     
     
     
  2. Water is a molecule, and its numerous bonds result in unique properties.
     
     
     
     
    • among water molecules and between water and other molecules.
       
       
       
       
    • High heat nearby air and ground temperatures and leads to cooling of wet surfaces.
       
       
       
       
    • Solid water is less than liquid water and floats, allowing life under frozen surfaces.
       
       
       
       
    • Water is a versatile and can dissolve substances which are either ionic or polar.
       
       
       
       
      • Substances too large to dissolve in water can form a , such as in the of a cell.
     
     
     
     
  3. Water can dissociate into H+ (hydrogen) and OH- (hydroxide) .
     
     
     
     
     
    
 
    
 
    
 
    
 
    
 
    
 
    
 
    
 
    
 
    
 
    
 
    
 
    
 
    
 
    
 
    
 
    
 
    
 
    
 
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