Chapter 16:
Oxidation-Reduction Reactions
Practice Test
1.
As ethanol is oxidized in a breathalyzer, chromium in orange dichromate ions is reduced to ________________.
a.
yellow Cr
4+
ions
b.
blue-green Cr
3+
ions
c.
colorless Cr
6+
ions
d.
black Cr atoms
Hint
2.
Luminol is used in a preliminary test for _______________.
a.
clay
b.
milk
c.
saliva
d.
blood
Hint
3.
Which type of can takes the longest to degrade?
a.
steel
b.
aluminum
c.
iron
d.
tin
Hint
4.
A reaction in which __________ are lost and gained is an oxidation-reduction reaction.
a. neutrons
b. hydrogen ions
c. protons
d. electrons
Hint
5.
Bleach removes stain from clothing by ___________ colored molecules.
a.
reducing
b.
protecting
c.
dissolving
d.
oxidizing
Hint
6.
The vitamin C in lemons is a/an ______________.
a.
oxidizing agent
b.
carbohydrate
c.
corrosive compound
d.
good antioxidant
Hint
7.
What chemical species is oxidized in the reaction represented by the unbalanced equation H
2
O
2
(l) + Br
-
(aq)
Br
2
(aq) + H
2
O(l)?
a.
O
-
b.
Br
-
c.
H
2
O
2
d.
H
2
O
2
Hint
8.
Sodium __________ when it reacts with sulfur to form sodium sulfide.
a.
gains one electron
b.
gains two electrons
c.
is oxidized
d.
is reduced
Hint
9.
Large deposits of solid, elemental __________ are formed in redox reactions near the vents of some volcanoes.
a.
hydrogen
b.
chlorine
c.
oxygen
d.
sulfur
Hint
10.
When sodium reacts with sulfur to form sodium sulfide, each sulfur atom ________________.
a.
loses one electron
b.
loses six electrons
c.
gains one electron
d.
gains two electrons
Hint
11.
_______ are reduced when black-and-white photographic film is exposed to light.
a.
Ag
1+
ions
b.
Br atoms
c.
Br
1-
ions
d.
Ag atoms
Hint
12.
What is the oxidizing agent in the reaction Cu(s) + 2AgNO
3
(aq)
2Ag(s) + Cu(NO
3
)
2
(aq)?
a.
Cu
b.
Ag
1+
c.
Ag(s)
d.
NO
3
1-
Hint
13.
What is the oxidation number of chlorine in KClO
3
?
a.
3+
b.
5+
c.
1-
d.
1+
Hint
14.
What chemical species is the reducing agent in the reaction described in question 23?
a.
Br
2
b.
Br
-
c.
H
2
O
2
d.
O
-
Hint
15.
What is the reducing agent in the reaction Cu(s) + 2AgNO
3
(aq)
2Ag(s) + Cu(NO
3
)
2
(aq)?
a.
Ag(s)
b.
Ag
1+
c.
Cu
d.
NO
3
1-
Hint
16.
The fixer used in black-and-white photography contains ________________.
a.
barium ions
b.
thiosulfate ions
c.
chloride ions
d.
sulfur atoms
Hint
17.
___________ reduces iron ore to iron in a blast furnace.
a.
calcium
b.
oxygen
c.
Carbon monoxide
d.
calcium carbonate
Hint
18.
What is the oxidation number of oxygen as a free element?
a.
1-
b.
0
c.
2-
d.
2+
Hint
19.
When aluminum metals reacts with the tarnish on silver, products of the reaction include ____________.
a.
Ag
+
and Al
b.
Ag and Al
3+
c.
Ag and H
+
d.
Al and OH
-
Hint
20.
Which element is oxidized in the reaction BaCl
2
(aq) + Na
2
SO
4
(aq)
2NaCl(aq) + BaSO
4
(s)?
a.
Na
b.
none
c.
Cl
d.
Ba
Hint
