Module 2

  1. water molecules are held together by
    polar covalent bonds
  2. water is thought of as a universal
  3. because oxygen greedily holds its electrons, they get pulled to the "oxygen" side and there is a relative positive charge on oxygen and a relative negative charge on hydrogen.... what is this an example of (partial)
  4. water is ________ dense as a solid than a liquid
    less; ice floats.
  5. ________ bonds hold the two complimentary strands of DNA together
  6. Ionic bonds are found in _______ and _______
    teeth; bones
  7. Covalent bonds form most important bonds in _______ and in the ________ of DNA and RNA molecules.
    Proteins; backbones
  8. when water is split to form H+ and OH- ions, the resulting charged ions contribute to 
  9. Oriented water molecules are
    hydration shells
  10. define surface tension
    a property that results from the cohesion of molecules to each other.
  11. detergents are
  12. _________ secreted by cells in the lung reduce surface tension.
  13. One end of a surfactant molecule likes grease, the other end likes
  14. without surfactant lungs cannot
  15. define capillary action
    results from the cohesive forces within the liquid and the adhesive forces between the liquid and the walls. If the adhesive force between the wall of the container and water is greater than the adhesive force between water molecules, then the water will "climb" the walls of the tube.
  16. In a solution, a substance is called the _______ dissolves another substance called the ________
    solvent; solute
  17. Usually there is more ________ than solute
  18. In human biology, the solvent is always
  19. If you dissolve sugar in water and it forms a sugar solution. What is the solvent and what is the solute
    • Solvent water
    • solute  sugar
  20. define a mole
    is just a convenient way of counting large numbers of small things
  21. 1 mole =
    6.02 x 1023
  22. What is Avagadro's number
    6.02 x 1023
  23. define colloids
    like solutions, except the particles are large enough to scatter light.
  24. define emulsion
    is a colloid where all components are liquid
  25. define suspension
    the particles are even larger than colloid, and these settle to the bottome of a container given time
  26. define acid
    a substance that dissolves in water to form one or more H+ ions and one or more anions
  27. define base
    is a substance that dissolves in water to form one or more OH- ions and one or more cations
  28. define salt
    is a substance that dissolves into ions. it does not form either H+ ions or OH- ions.... examples NaCl, KCl, CaCO3
  29. acids in the human body include
    • gastric juice
    • vaginal fluid
    • urine (most of the time)
    • saliva
  30. bases in the human body include
    • urine (only rarely)
    • blood
    • semen
    • cerebrospinal fluid
    • pancreatic juice
    • bile
  31. the most important buffer system in human biology is the
    carbonic acid-bicarbonate buffer system
  32. define pH
    negative logarithm of the hydrogen ion concentration

  33. weak acids and weak bases are important components of a special type of solutions called
    a buffer
  34. define strong acid
    practically all HCl molecules break apart into H+ and Cl- ions when we put HCl into water.
  35. what are commonly encountered strong acids
    Hydrochloric acid  HCl

    Sulfuric acid   H2SO4

    Nitric acid  HNO3
  36. define strong base
    because almost all KOH molecules break apart into K+ and OH- when we dissolve KOH in water
  37. What are strong bases
    • NaOH
    • KOH
Card Set
Module 2