chapter 2

  1. a water molecule is polar because its hydrogen and oxygen atoms
    do not share the elcetrons equally
  2. changing the course or pathway of a chemical reaction so that it requires less activation energy
    is aaccomplished by the action of catalysts on reactants
  3. atoms are composed of
    • protons witha positive charge
    • neutrons with no charge
    • electrons witha negative charge
  4. a molecule that has a partial posibive charge on one side and partial negative charge on the other side is called a
    polar molecule
  5. atoms become more stable when they form compunds because
    their outer orbitals become filled when they form compunds
  6. the term base and alkaline refer to solutions that
    contain more hydroide ions than hydronium ions
  7. polar molecules such as water have
    both negative and positive poles
  8. matter in the universe is composed of
  9. the bond formed when two atoms share a pair of electrons is called a
    covalent bond
  10. an atom that has gained or lost electrons is called an
  11. what tend to prevent great fluctions in pH?
  12. the eltrons of an atom
    orbit the nucleus in various energy levels
  13. the smallest particle of c arbon that can retain the chemical properties of carbon is
    a carbon atom
  14. a neutral soulution has an equal number of
    hydroide and hydronium ions
  15. what are able to heat up molecules so that they can react?
  16. a soulution wiht a pH of 11 is
  17. water is a polar molecule because
    different parts of the molecule have lsightly different charges
  18. a single organism may contain
    thousands of different enzymes, each on specific to a different chemical reacton
  19. atoms that have gained energy
    have electrons that move to higher energy levels
  20. what charcteristics of fwater is a result of hydrogen bonding?
    • cohesive strength
    • capillarity
    • adhesive strength
  21. which of the follwing states of matter contain particles that are tightly linked together in a definite shape?
  22. because carbon has four electrons in its outer energy level,
    it can react with up to four other atoms to form a covalent bonds
  23. a substance that is composed of oonly one type of atom is called
  24. acidic soulutions have a pH that is
    less than 7
  25. oxidation-reduction reactions are important in organisms because th ey
    allow the passage of energy from molecule to molecule
  26. when a molecule gains an electron it has been
  27. the concentration of a soulution is
    the amount of solute that is dossolved ina fixed amount of a solution
  28. substances that re hccanged when they become involved in chemical reactions are calle d_______ while the new substances that are formed are called ____?
    reactions, product
  29. the loss of electroins form a molecule is called_______, while the gain of electrons by a molecule is called______
    oxidation, redoction
  30. ________and_______ions form when water dissociates?
    hydrogen and hydroxide
  31. a substance that dissolves in another is called________
  32. _________is the most common solvent in cells
  33. buffers are important becasue body fluids must be maintained within a relatively narrow range of ___?
  34. an acidic solution is one that has more___than______ ions
    hydronium, hydroxide
  35. the energy needeed to break existing chemical bonds during the initiation of chemical reaction is called_______
    activation energy.
  36. water is very effective at dissolving other polar substances because of its_____?
Card Set
chapter 2