Download Ch19 worksheet answer key

Sharjah Educational Zone
Sama American Private School
Science Department (Chemistry)
1st Term 2020 – 2021
Worksheet 6
Grade 12
Oxidizing and Reducing Agents
Q1.Answer the following questions in the space provided
1. For each of the following, identify the stronger oxidizing or reducing agent.
a.
Ca or Cu as a reducing agent
b.
Ag+ or Na+ as an oxidizing agent
c.
Fe3+ or Fe2+ as an oxidizing agent
2. For each of the following incomplete equations, state whether a redox reaction is likely to
occur. (Refer to Figure 3.2 of the text.)
a.
Mg + Sn2+  will occur and the product are Mg+2 + Sn
b.
Ag + Cu2+  no reaction
c.
Br2 + I  reaction will occur and the product is 2Br- + I2
3. Label each of the following statements about redox as True or False.
a. A strong oxidizing agent is itself readily reduced.
(True)
b. In disproportionation, one chemical acts as both an oxidizing agent and a reducing agent
in the same process.
(True)
c. The number of moles of chemical oxidized must equal the number of moles
chemical reduced.
(False)
of
Q2. Answer the following problems.
4.Solutions of Fe2+ are fairly unstable, in part because they can undergo disproportionation,
as shown by the following unbalanced equation:
3Fe2+  2Fe3+ + Fe
a. Balance the above equation.
5.
a.
Oxygen gas is a powerful oxidizing agent.
Assign the oxidation number to O2.
Pure Element so 0
b.
What does oxygen’s oxidation number usually become when it functions as an
oxidizing agent?
-2
c. Approximately where would you place O2 in the list of oxidizing agents in Figure 3.2 of the
text?
At the bottom of the column of oxidizing agents
d. Describe the changes in oxidation states that occur in carbon and oxygen, and identify the
oxidizing and reducing agents, in the combustion reaction described by the following
equation:
C6H12O6(s) + 6O2(g)  6CO2(g) + 6H2O(l)
Each O atom in O2 changes from the oxidation state of 0 to 2 in CO2 and H2O.
Oxygen is reduced; therefore, it is the oxidizing agent. Each C atom in C6H12O6 as a reactant is in the
oxidation state of 0, and in CO2 as a product, it is +4. It is oxidized and is therefore the reducing agent.