CHAPTER 2—LIFE, CHEMISTRY, AND WATER
MULTIPLE CHOICE
1. According to studies by Norman Terry and coworkers, some plants can perform a version of
bioremediation of selenium in wastewater by
a.
converting selenium to a form that kills waterfowl.
b.
using selenium to make a necessary supplement for humans.
c.
converting selenium into a relatively nontoxic gas.
d.
storing selenium in the soil.
e.
increasing the selenium concentration in the water.
2. The laws of chemistry and physics that govern living things are ____ the laws of chemistry and
physics that govern nonliving things.
a.
different from
b.
the same as
c.
roughly half the same as and half different from
d.
mostly different from
e.
mostly the same as
3. A substance that cannot be broken down into simpler substances by ordinary chemical or physical
techniques is a(n) ____.
a.
molecule
b.
chemical
c.
compound
d.
element
e.
biological compound
4. Four elements make up more than 96% of the mass of most living organisms. Which of the following
is NOT one of those four elements?
a.
sodium
b.
carbon
c.
oxygen
d.
nitrogen
e.
hydrogen
5. A trace element is one found in specific organisms in ____ quantities and is ____ for normal biological
functions.
a.
moderate; unnecessary
b.
moderate; vital
c.
small; unnecessary
d.
large; unnecessary
e.
small; vital
6. The smallest unit that retains the chemical and physical properties of an element is a(n) ____.
a.
proton
b.
compound
c.
molecule
d.
neutron
e.
atom
7. The substance H2O is considered to be
a.
both a molecule and a compound.
b.
a compound but not a molecule.
c.
neither a molecule nor a compound.
d.
a molecule but not a compound.
e.
a chemical but not biological molecule.
8. The substance O2 is considered to be
a.
both a molecule and a compound.
b.
a compound but not a molecule.
c.
neither a molecule nor a compound.
d.
a molecule but not a compound.
e.
a chemical but not a biological molecule.
9. An oxygen atom has ____ surrounding a nucleus composed of ____.
a.
neutrons; electrons and protons
b.
electrons; protons and neutrons
c.
protons and electrons; neutrons
d.
protons; neutrons and electrons
e.
electrons and neutrons; protons
Use the figure above for the following question(s).
10. The mass number of the atom depicted in the figure is
a.
5.
b.
7.
c.
8.
d.
15.
e.
22.
11. The atomic number of the atom depicted in the figure is
a.
5.
b.
7.
c.
8.
d.
15.
e.
22.
12. The number of electrons for the atom depicted in the figure is
a.
5.
b.
7.
c.
8.
d.
15.
e.
22.
13. The number of neutrons for the atom depicted in the figure is
a.
5.
b.
7.
c.
8.
d.
15.
e.
22.
14. Which of the following are charged particles?
a.
electrons and protons
b.
neutrons only
c.
protons and neutrons
d.
electrons only
e.
protons, neutrons, and electrons
15. What is the atomic mass number of an atom with 7 electrons, 7 neutrons, and 7 protons?
a.
7 daltons
b.
10 daltons
c.
14 daltons
d.
21 daltons
e.
28 daltons
16. Isotopes of the same element differ from each other in the number of
a.
electrons and protons.
b.
neutrons only.
c.
protons and neutrons.
d.
electrons only.
e.
protons, neutrons, and electrons.
17. A carbon atom with six protons, seven neutrons, and six electrons has a mass number of
a.
6.
b.
7.
c.
12.
d.
13.
e.
19.
18. Which element would the element lithium most likely form an ionic bond with?
a.
Aluminum; atomic number = 13
b.
Chlorine; atomic number = 17
c.
Magnesium; atomic number = 12
d.
Nitrogen; atomic number = 7
e.
Silicon; atomic number = 14
19. 14C is heavier than 12C because it has ______.
a.
two more electrons than 12C
b.
two more neutrons than 12C
c.
two more protons than 12C
d.
one more proton and one more electron than 12C
e.
one more proton and one more neutron than 12C
20. The isotope 14C undergoes radioactive decay with a neutron splitting into an electron and a proton.
This decay produces an atom of
a.
iron.
b.
carbon.
c.
hydrogen.
d.
oxygen.
e.
nitrogen.
21. An orbital describes the ____ of an electron.
a.
exact location
b.
exact path
c.
most frequent locations
d.
charge
e.
chemical bonds
Use the figure above for the following question(s).
22. The electrons at the lowest energy level in the neon atom depicted in the figure above are found in
which orbital?
a.
1s
b.
2s
c.
2px
d.
2py
e.
2pz
23. All of the orbitals shown in the neon atom in the figure are completely filled with electrons. How
many electrons does this neon atom have?
a.
5
b.
6
c.
8
d.
10
e.
16
24. Under the right conditions, an electron can
a.
move to a lower energy level.
b.
enter an orbital shared by two atoms.
c.
move to a higher energy level.
d.
move from one atom to another atom.
e.
all of these
25. Sodium has one valence electron in its third energy level. To reach a stable energy configuration,
sodium will tend to
a.
take up an electron from another atom.
b.
move its valence electron to the second energy shell.
c.
give up an electron to another atom.
d.
share its valence electron with another atom.
e.
move an electron from the second energy level to the valence shell.
26. Which of the following is most likely to share electrons with other atoms in joint orbitals?
a.
chlorine (7 valence electrons)
b.
calcium (2 valence electrons)
c.
argon (8 valence electrons)
d.
carbon (4 valence electrons)
e.
potassium (1 valence electron)
27. Which of the following is likely to be chemically unreactive?
a.
chlorine (7 valence electrons)
b.
calcium (2 valence electrons)
c.
argon (8 valence electrons)
d.
carbon (4 valence electrons)
e.
potassium (1 valence electron)
28. Which of the following is most likely to take up an electron from another atom?
a.
chlorine (7 valence electrons)
b.
calcium (2 valence electrons)
c.
neon (8 valence electrons)
d.
carbon (4 valence electrons)
e.
potassium (1 valence electron)
29. Radioactive ____ is commonly used to treat patients with dangerously overactive thyroid glands.
a.
carbon
b.
radium
c.
iodine
d.
thallium
e.
cobalt
30. In radiation therapy, cancer cells are killed by ____.
a.
carbon
b.
radium
c.
iodine
d.
thallium
e.
nitrogen
31. The chemical bonds that form when atoms that have lost electrons are electrically attracted to atoms
that have gained electrons are called ____.
a.
polar covalent bonds
b.
van der Waals forces
c.
ionic bonds
d.
hydrogen bonds
e.
nonpolar covalent bonds
32. The chemical bonds that are formed when atoms share electrons equally are called ____.
a.
polar covalent bonds
b.
van der Waals forces
c.
ionic bonds
d.
hydrogen bonds
e.
nonpolar covalent bonds
28
33. The chemical bonds that are formed when atoms share electrons unequally are called ____.
a.
polar covalent bonds
b.
van der Waals forces
c.
ionic bonds
d.
hydrogen bonds
e.
nonpolar covalent bonds
34. The chemical bonds that are formed when atoms with temporary zones of positive charge are attracted
to other atoms with temporary zones of negative charge are called ____.
a.
polar covalent bonds
b.
van der Waals forces
c.
ionic bonds
d.
hydrogen bonds
e.
nonpolar covalent bonds
35. Chemical bonds that are formed when one atom with a partial positive charge (created from unequal
sharing of electrons) is electrically attracted to another atom with a partial negative charge (also
created from unequal sharing of electrons) are called ____.
a.
polar covalent bonds
b.
van der Waals forces
c.
ionic bonds
d.
hydrogen bonds
e.
nonpolar covalent bonds
36. Which of the following types of chemical linkages is the weakest?
a.
polar covalent bonds
b.
van der Waals forces
c.
ionic bonds
d.
hydrogen bonds
e.
nonpolar covalent bonds
37. The attraction between Na+ cations and Cl− anions forms ____ that hold together the compound NaCl.
a.
polar covalent bonds
b.
van der Waals forces
c.
ionic bonds
d.
hydrogen bonds
e.
nonpolar covalent bonds
38. Geckos are able to cling to vertical walls due to ____.
a.
polar covalent bonds
b.
van der Waals forces
c.
ionic bonds
d.
hydrogen bonds
e.
nonpolar covalent bonds
39. Molecules such as H−H and O=O are held together by ____.
a.
polar covalent bonds
b.
van der Waals forces
c.
ionic bonds
d.
hydrogen bonds
e.
nonpolar covalent bonds
40. The molecule shown in the figure above is held together by ____.
a.
polar covalent bonds
b.
van der Waals forces
c.
ionic bonds
d.
hydrogen bonds
e.
nonpolar covalent bonds
41. Metallic ions such as Ca2+, Na+, and Fe3+ readily form ____.
a.
polar covalent bonds
b.
van der Waals forces
c.
ionic bonds
d.
hydrogen bonds
e.
nonpolar covalent bonds
42. The chemical linkages that exert an attractive force over the greatest distance are ____.
a.
polar covalent bonds
b.
van der Waals forces
c.
ionic bonds
d.
hydrogen bonds
e.
nonpolar covalent bonds
43. In contrast to ionic bonds, covalent bonds ____.
a.
hold atoms together
b.
have distinct, three-dimensional forms
c.
transfer electrons from one atom to another
d.
are relatively weak
e.
are transient
44. The dotted line in the figure above indicates ____.
a.
a polar covalent bond
b.
van der Waals forces
c.
an ionic bond
d.
a hydrogen bond
e.
a nonpolar covalent bond
45. In a molecule of methane, CH4, each hydrogen atom shares an orbital with the carbon atom. The total
number of shared electrons in CH4 is ____.
a.
4
b.
2
c.
1
d.
8
e.
5
46. A polar covalent bond would be most likely to form between
a.
atoms with different electronegativities.
b.
cations and anions.
c.
atoms with + and − charges.
d.
atoms with filled valence shells.
e.
atoms of the same element.
47. Which of these types of chemical bonds would you not expect to find in biological molecules?
a.
covalent bonds
b.
van der Waals forces
c.
ionic bonds
d.
hydrogen bonds
e.
all of these types of bonds are found in biological molecules
48. In the presence of water, nonpolar associations form between molecules or regions of molecules that
are ____.
a.
partially charged
b.
hydrophobic and hydrophilic
c.
hydrophobic
d.
fully charged
e.
hydrophilic
49. A mixture of vegetable oil and water will separate into layers because oil is ____ and forms ____.
a.
hydrophobic; nonpolar associations
b.
hydrophilic; nonpolar associations
c.
hydrophilic; polar associations
d.
hydrophobic; polar associations
e.
hydrophobic; ionic associations
50. Analyze this chemical reaction:
6 CO2 + 6 H2O → C6H12O6 + 6 O2
Which of the following is FALSE?
a.
Water is a reactant.
b.
C6H12O6 is a product.
c.
Molecular oxygen is a product.
d.
CO2 is a reactant.
e.
Molecular carbon is a reactant.
51. The formation and breaking of bonds between atoms requires
a.
a chemical reaction.
b.
van der Walls forces.
c.
partial charges.
d.
an empty valence shell.
e.
an enzyme.
52. What do cohesion, surface tension, and specific heat have in common concerning the properties of
water?
a.
All are produced by covalent bonding.
b.
All are properties related to hydrogen bonding.
c.
All have to do with nonpolar covalent bonds.
d.
All increase when temperature increases.
e.
All are produced by covalent bonding and all increase when temperature increases.
53. A molecule of water in the middle of a chunk of ice will usually have ____ hydrogen bonds with other
water molecules.
a.
3
b.
3.4
c.
6
d.
4
e.
2