Deck 10: Oxidation-Reduction Reactions

Question 1

Charge is transported from place to place in a battery by

A) an anode
B) a cathode
C) the migration of ions
D) an external electrical circuit

Answer 1

the migration of ions

Question 2

In a fuel cell using oxygen as the oxidizer and hydrogen as the fuel, what is the overall cell reaction?

A) H₂O $\rightarrow$ H₂ + O₂
B) 2 H₂ + O₂ $\rightarrow$ 2 H₂O
C) H₂O + 4 e^- $\rightarrow$ 2 H₂ + 4 OH^-
D) O2 + 4 H⁺ + 4 e^- $\rightarrow$ 2 H₂O

Answer 2

2 H₂ + O₂ $\rightarrow$ 2 H₂O

Question 3

Which of the following is a reduction of carbon?

A) C + 2 H₂ $\rightarrow$ CH₄
B) C + O₂ $\rightarrow$ CO₂
C) 2 C + O₂ $\rightarrow$ 2 CO
D) C²⁺ $\rightarrow$ C⁴⁺ + 2e^-

Answer 3

C + 2 H₂ $\rightarrow$ CH₄

Question 4

In the equation 2 Na(s) + Cl₂(g) $\rightarrow$ 2 Na⁺ + 2 Cl^-, the oxidizing agent is

A) Na(s)
B) Cl₂(g)
C) Na⁺
D) Cl^-

Question 5

In the electrolysis reaction, oxidation occurs at which electrode?

A) cathode
B) anode
C) both electrodes
D) neither electrode

Question 6

In the equation SnO₂(g) + 2 C(s) $\rightarrow$ Sn(s) + 2 CO(g), what substance is the reducing agent?

A) SnO₂
B) C
C) Sn
D) CO

Question 7

A battery which may be recharged is called a(n)

A) primary battery
B) dry cell
C) electroplating cell
D) secondary battery

Question 8

Which of the following is not a definition of reduction?

A) gain of electrons
B) gain of protons
C) gain of hydrogen
D) loss of oxygen

Question 9

Antioxidant vitamins

A) react with DNA
B) donate electrons to free radicals
C) are reduced
D) form free radicals in the body

Question 10

Which one of the following will not combine with oxygen?

A) nitrogen
B) aluminum
C) hydrogen
D) helium

Question 11

In a lead storage battery, what lead compound is formed at both the cathode and the anode during discharge?

A) lead oxide (PbO₂)
B) lead chloride (PbCl₂)
C) lead sulfate (PbSO₄)
D) lead oxide (PbO)

Question 12

Which of the following might prevent corrosion of iron?

A) a water spray
B) a coating of zinc
C) acid treatments
D) salt solutions

Question 13

PbSO₄, Pb, and H₂SO₄ are chemicals in

A) dry cell
B) primary battery
C) salt bridge
D) automobile battery

Question 14

Reducing agents

A) gain electrons and get oxidized
B) lose electrons and get reduced
C) gain electrons and get reduced
D) lose electrons and get oxidized

Question 15

Free radicals are particles that

A) have an unpaired electron
B) act as oxidizing agents
C) grab another electron from a neighboring molecule
D) all of the above

Question 16

Which is not an example of a primary battery?

A) lead-acid automobile battery
B) alkaline battery
C) mercury battery
D) lithium battery

Question 17

Which of the following is not a definition of oxidation?

A) loss of electrons
B) loss of hydrogen
C) loss of protons
D) addition of oxygen

Question 18

Which equation does not fit the definition of oxidation?

A) Ag⁺ + e^- $\rightarrow$ Ag
B) C₂H₆ $\rightarrow$ H₂ + C₂H₄
C) C + O₂ $\rightarrow$ CO₂
D) Na $\rightarrow$ Na⁺ + e^-

Question 19

When a zinc strip is placed in a copper sulfate solution,

A) the copper solution will lose its blue color
B) the zinc will dissolve
C) black crystals of copper atoms appear
D) all of the above occur

Question 20

Which of the following is not necessary for corrosion of iron?

A) iron
B) water
C) light
D) oxygen

Question 21

Electrolysis

A) is the process of producing electricity
B) uses electrical energy to produce chemical change
C) is used to reduce aluminum ore to pure metal
D) both a and c

Question 22

Which of the following is not an antioxidant vitamin?

A) vitamin A
B) vitamin D
C) vitamin C
D) vitamin E

Question 23

Identify the reduced species in the following equation CH₄(g) + 2O₂(g) $\rightarrow$ CO₂(g) + 2H₂O(g)

A) C
B) O₂(g)
C) H
D) H₂O

Question 24

Which of the following is a free radical?

A) ozone, O₃
B) fluorine, F₂
C) chlorine, Cl₂
D) nitrogen dioxide, NO₂

Question 25

Which of the batteries listed below is a primary battery?

A) lithium ion battery
B) alkaline battery
C) Ni-Cad battery
D) lead acid battery

Question 26

Which molecule would be a good reducing agent?

A) O₂
B) O₃
C) H₂
D) H₂O₂

Question 27

Which of the batteries listed below is a reusable battery?

A) dry cell battery
B) mercury battery
C) alkaline battery
D) lead storage battery

Question 28

Identify the oxidized species in the following equation 4Al(s) + 3O₂(g) $\rightarrow$ 2Al₂O₃(s)

A) Al(s)
B) O₂(g)
C) Al³⁺
D) O^2-

Question 29

What is a bleaching agent?

A) oxidizes colored chemicals
B) reduces colored chemicals
C) oxidizes bleach
D) removes salts from hard water

Question 30

Oxidation always occurs

A) with the loss of electrons
B) with the gain of electrons
C) with the gain of hydrogen
D) only for metal atoms and not ions

Question 31

Which molecule would be a good oxidizing agent?

A) H₂
B) SO₂
C) C
D) H₂O₂

Question 32

Which of the following is a free radical?

A) SO₂
B) SO₃
C) NO
D) N₂O