Matching
|
|
|
Match each item with the correct statement below. a. | oxidation
number | c. | oxidizing
agent | b. | half-reaction | d. | reducing agent | | | | |
|
|
|
1.
|
substance that accepts electrons
|
|
|
2.
|
substance that donates electrons
|
|
|
3.
|
integer related to the number of electrons under an atom's control
|
|
|
4.
|
reaction showing either the reduction or the oxidation reaction
|
Multiple Choice
Identify the
letter of the choice that best completes the statement or answers the question.
|
|
|
5.
|
If an
atom is reduced in a redox reaction, what must happen to another atom in the system? a. | It must be
oxidized. | b. | It must be reduced. | c. | It must be
neutralized. | d. | Nothing needs to happen to another atom in the
system. | | |
|
|
|
6.
|
What
is another name for an oxidation-reduction reaction? a. | O-reaction | c. | redox
reaction | b. | R-reaction | d. | oxred reaction | | | | |
|
|
|
7.
|
When
iron oxide becomes iron, what type of reaction occurs? a. | oxidation | c. | neutralization | b. | reduction | d. | combination | | | | |
|
|
|
8.
|
Oxidation is ____. a. | a loss of oxygen | c. | a loss of electrons | b. | a gain of
electrons | d. | a gain of
hydrogen | | | | |
|
|
|
9.
|
What
are transferred in an oxidation-reduction reaction? a. | protons | c. | electrons | b. | ions | d. | atoms | | | | |
|
|
|
10.
|
In
the reaction of sodium with oxygen, which atom is reduced? a. | sodium | c. | both a and
b | b. | oxygen | d. | neither a nor
b | | | | |
|
|
|
11.
|
Cu ® Cu + 2
e-
The equation above represents the type of reaction called ____. a. | redox | c. | reduction | b. | hydrolysis | d. | oxidation | | | | |
|
|
|
12.
|
Which
type of reaction does Sn ® Sn represent? a. | oxidation | c. | hydrolysis | b. | reduction | d. | none of the above | | | | |
|
|
|
13.
|
What
is the reducing agent in the following reaction?
2Na + 2H O ® 2NaOH + H a. | Na | c. | NaOH | b. | H O | d. | H | | | | |
|
|
|
14.
|
What
is the reducing agent in the following reaction?
2Na + S
® Na S a. | Na | c. | Na S | b. | S | d. | Na | | | | |
|
|
|
15.
|
What
is the oxidizing agent in the following reaction?
|
|
|
16.
|
Which
statement is true about the following reaction?
(Hint: Chlorine
is the more electronegative element.) a. | Sulfur is reduced to SCl . | c. | Chlorine is
oxidized to SCl . | b. | Chlorine is reduced to SCl . | d. | Sulfur is the
oxidizing agent. | | | | |
|
|
|
17.
|
What
is the oxidizing agent in the following reaction?
|
|
|
18.
|
The
oxidation number of magnesium in magnesium chloride is ____.
|
|
|
19.
|
The
oxidation number of hydrogen when it is in a compound other than a hydride is ____.
|
|
|
20.
|
The
oxidation number of bromime in bromime gas is ____.
|
|
|
21.
|
The
oxidation number of sulfur in each of the following is +6 EXCEPT for ____.
|
|
|
22.
|
In
which of the following compounds is the oxidation number of nitrogen different from the other
three?
|
|
|
23.
|
Identify the atom that increases in oxidation number in the following redox
reaction.
2MnO + 2K CO + O  2KMnO + 2CO
|
|
|
24.
|
Which
atom has a change in oxidation number of –3 in the following redox
reaction?
K Cr O +
H O + S  KOH + Cr O + SO
|
|
|
25.
|
In
the following unbalanced reaction, which atom is reduced?
a. | hydrogen | c. | chlorine | b. | oxygen | d. | sulfur | | | | |
|
|
|
26.
|
In
the following unbalanced reaction, which atom is oxidized?
a. | hydrogen | c. | oxygen | b. | nitrogen | d. | bromine | | | | |
|
|
|
27.
|
Which
element increases its oxidation number in the following reaction?
a. | potassium | b. | hydrogen | c. | oxygen | d. | No element increases its oxidation
number. | | |
|
|
|
28.
|
Which
element decreases its oxidation number in the following reaction?
a. | iodine | b. | potassium | c. | chlorine | d. | No element
decreases its oxidation number. | | |
|
|
|
29.
|
Which
of the following reactions is a redox reaction? a. | acid-base | c. | combustion | b. | double-replacement | d. | all of the above | | | | |
|
|
|
30.
|
What
coefficient of H balances the atoms in the following half-reaction?
|
|
|
31.
|
What
is the reduction half-reaction for the following unbalanced redox
equation?
|
|
|
32.
|
What
is the oxidation half-reaction for the following unbalanced redox equation?
|
|
|
33.
|
What
is the reduction half-reaction in the following unbalanced equation?
|
|
|
34.
|
Which
of the following is an oxidation half-reaction?
|
Short Answer
|
|
|
35.
|
Balance the following redox equation using the oxidation-number-change method. Show
all your work.
|
Numeric Response
|
|
|
36.
|
What
is the oxidation number of magnesium in magnesium iodide?
|
|
|
37.
|
What
is the change in oxidation number of chromium when Na Cr O
becomes CrI ?
|
|
|
38.
|
What
is the change in oxidation number of manganese when MnO becomes Mn O ?
|
Essay
|
|
|
39.
|
Explain how to identify the reducing agent in a reaction of magnesium with
oxygen.
|
|
|
40.
|
Explain how to determine which substances are oxidized and which are reduced in the
following reaction.
H O(l) +
Br (g) + SO2(g) 
HBr(aq) + H SO (aq)
|