| Questions |
Answers |
Explanantions |
| 41. Which equation represents
a double replacement reaction?
A.
B.
C.
D.
|
C |
positive
ions switch with the negative ions |
| 42. What is the molecular
formula of a compound that has a molecular mass of 54
and the empirical formula C2H3?
A. C2H3
B. C4H6
C. C6H9
D. C8H12
|
B |
C4H6
has a mass of 54 and can be reduced to C2H3 |
| 43. Given the diagrams X, Y,
and Z below:
Which diagram or diagrams represent a mixture of
elements A and B?
A. X, only
B. Z, only
C. X and Y
D. X and Z
|
B |
X is a
compound
Y is a diatomic element
Z is 2 diatomic elements |
| 44. Which is an electron
configuration for an atom of chlorine in the excited
state?
A. 2–8–7
B. 2–8–8
C. 2–8–6–1
D. 2–8–7–1
|
C |
17
electrons with 1 promoted to a higher level |
| 45. Based on the nature of the
reactants in each of the equations below, which reaction
at 25°C will occur at the fastest rate?
A.
B.
C.
D.
|
B |
ionic
substances dissolved react the fastest
|
| 46. Given the reaction at
equilibrium:
The concentration of A(g) can be increased by
A. lowering the temperature
B. adding a catalyst
C. increasing the concentration of AB(g)
D. increasing the concentration of B(g)
|
C |
LeChatelier-
adding to one side shifts the
equilibrium to the other
taking away will bring it back
temp is heat |
| 47. Which structural formula
represents an alcohol?
A.
B.
C.
D.
|
B |
-OH
alcohol |
| 48. A voltaic cell differs
from an electrolytic cell in that in a voltaic cell
A. energy is produced when the reaction occurs
B. energy is required for the reaction to occur
C. both oxidation and reduction occur
D. neither oxidation nor reduction occurs
|
A |
voltaic
is a battery
electrolytic requires one |
| 49. What is the purpose of the
salt bridge in a voltaic cell?
A. It blocks the flow of electrons.
B. It blocks the flow of positive and negative ions.
C. It is a path for the flow of electrons.
D. It is a path for the flow of positive and negative
ions.
|
D |
ion flow
(salt--- ions) |
| 50. According to Reference
Table N, which radioactive isotope will retain only
1/8 its original radioactive atoms after
approximately 43 days?
A. gold-198
B. iodine-131
C. phosphorus-32
D. radon-222
|
C |
1/8= 3
(1/2 lives)
43days/3= 14.3d
P-32 |