Download Redox Reactions Test Review

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Redox Reactions Test Review
Part 1: Oxidation Numbers
1. What is the oxidation number for any neutral, uncombined element?
2. What is the common oxidation number for oxygen? What is the oxidation number for oxygen in
H2O2 (the exception)?
3. What is the oxidation number for hydrogen in a metal hydride (ex. NaH, CaH2)?
4. Assign the oxidation number for each element in the following:
a. N2O4
N=
O=
b. CO32-
C=
O=
c. H2
H=
d. NO2
N=
O=
e. CrO42-
Cr =
O=
f. Cr2O72-
Cr =
O=
g. SO42-
S=
O=
h. SO32-
S=
O=
i.
SO3
S=
O=
j.
SO2
S=
O=
k. N2
N=
l.
NO2
N=
O=
m. NH3
N=
H=
n. N2O3
N=
O=
Part 2: Oxidation and Reduction
5. Define an oxidation and reduction (redox) reaction
6. In oxidation, what happens to the oxidation number? Does the element gain or lose electrons?
7. In reduction, what happens to the oxidation number? Does the element gain or lose electrons?
8. In a redox reaction, ClO4-1 is changed to Cl-1.
a. Are electrons lost or gained by chlorine?
b. How many electrons are lost or gained by chlorine?
9. Define spectator ion.
10. In the equation Ni + 2 HCl  NiCl2 + H2 label the following
a. Oxidized:
b. Reduced:
c. Spectator Ion:
11. In the equation Ca2+ + 2 Li  Ca + 2 Li+ label the following
a. Oxidized:
b. Reduced:
12. In the equation 2 C2H6 + 7 O2  4 CO2 + 6 H2O label the following
a. Oxidized
b. Reduced