The element present in all organic molecules is _________.
a) hydrogen
b) oxygen
c) carbon
d) nitrogen
c
Stanley Miller’s 1953 experiments supported the hypothesis that _______.
A) life arose on Earth from simple inorganic molecules.
B) organic molecules can be synthesized abiotically under conditions that may have existed on early Earth.
C) life arose on Earth from simple organic molecules, with energy from lightning and volcanoes.
D) the conditions on early Earth were conducive to the origin of life.
E) the conditions on early Earth were conducive to the abiotic synthesis of organic molecules.
b
When Stanley Miller applied heat and electrical sparks to a mixture of simple inorganic compounds such as methane, hydrogen gas, ammonia, and water vapor, what compounds were produced?
A) mostly amino acids
B) only simple organic compounds such as formaldehyde and cyanide
C) mostly hydrocarbons
D) only simple inorganic compounds
E) both simple organic compounds and more complex organic compounds such as amino acids and hydrocarbons
e
How many electron pairs does carbon share to complete its valence shell?
A) 1
B) 2
C) 3
D) 4
E) 8
d
A carbon atom is most likely to form what kind of bond(s) with other atoms?
A) ionic
B) hydrogen
C) covalent
D) covalent bonds and hydrogen bonds
E) ionic bonds, covalent bonds, and hydrogen bonds
c
The two molecules shown in the figure below are best described as ________.
H
|
H—C—H
H H H H |
| | | | | | |
H—C— C — C — C —H H—C — C — C—H
| | | | | | |
H H H H H H H
b) structural isomers
...
The figure above shows the structures of glucose and fructose. These two molecules differ in the ________. (Glucose and Fructose)
A) number of carbon, hydrogen, and oxygen atoms.
B) types of carbon, hydrogen, and oxygen atoms.
C) arrangement of carbon, hydrogen, and oxygen atoms.
D) number of oxygen atoms joined to carbon atoms by double covalent bonds.
E) number of carbon, hydrogen, and oxygen atoms; the types of carbon, hydrogen, and oxygen atoms; and the arrangement of carbon, hydrogen, and oxygen atoms.
c
the figure above shows the structure s of glucose and fructose. These two molecules are ______.
A) geometric isotopes.
B) enantiomers.
C) cis-trans isomers.
D) structural isomers.
E) nonisotopic isomers.
d
Which of the pairs of molecular structures shown below depict enantiomers (enantiomeric forms) of the same molecule?
c)
...
Which of the functional groups below acts most like an acid in water?
c) carboxyl
...
Which chemical group can act as an acid?
c) carboxyl
...
What is the name of the functional group shown in the figure below?
O
//
R—C
\
O—H
d) Carboxyl
...
Which functional group shown above is characteristic of alcohols?
a) A. -OH
...
Which functional group(s) shown above is (are) present in all amino acids?
B. O C. —NH2
||
—C—O—H
d) B and C
...
Which molecule shown above would have a positive charge in a cell?
d) H H
| /
H—C—N
| \
H H
...