THE ANSWER OF REDOX REACTION QUIZ Part I

1.Which substance is being oxidized in the following reaction?
2HCl(aq) + Zn(s) --> ZnCl2(aq) + H2(g)
Answer : c) Zn(s)
2.What is the oxidation number of Cr in K2Cr2O7?
Answer : d) +6
3.Given the following incomplete redox reaction, balance this equation in ACID solution with the set of smallest whole number coefficient:
Zn(s) + NO3-(aq) --> Zn2+(aq) + N2(g)
Identify the CORRECT statement below:
Answer : b) Zn(s) and NO3- react in a 5 to 2 mole ratio, respectively.
4.Which oxidation number is INCORRECTLY identified?
Answer : a) the oxidation number of P in phosphorus acid, H3PO3is +5
5.Which of the following is the INCORRECT statement?
Answer : c) The oxidizing agent in a redox reaction is oxidized.
6.In the reaction below, the oxidizing agent is ….
2NaCl + 2H2SO4 + MnO2 → Na2SO4 + MnSO4 + 2H2O + Cl2
Anawer : a.Mn4+
7.Which substance is being reduced in the following reaction?
14H+(aq) + Cr2O72- (aq) + 6Fe2+(aq) --> 2Cr3+(aq) + 6Fe3+(aq) + 7 H2O
Answer : e)Cr2O72-
8.Given the reaction:
4 HCl(aq) + MnO2(s)--> MnCl2(aq) + 2 H2O(l) + Cl2(g)
The manganese is ….
Answer : a) reduced and its oxidation number changes from +4 to +2
9.Given the reaction:
Pb(s) + Cu2+(aq) --> Pb2+(aq) + Cu(s)
What is the reducing agent?
Answer : c) Pb(s)
10.What occurs when an atom is oxidized in a chemical reaction?
Answer : b)a loss of electrons and an increase in oxidation number
11.Given the reaction:
3 Sn4+(aq) + 2 Cr(s) --> 3 Sn2+(aq) + 2 Cr3+(aq)
Which half-reaction represents the reduction that occurs?
Answer : a)Sn4+(aq) + 2 e- --> Sn2+(aq)
12.Given the reaction:
Zn(s) + 2 HCl(aq) --> ZnCl2(aq) + H2(g)
Which substance is oxidized?
Answer : a) Zn(s)
13.A redox reaction always demonstrates the conservation of ….
Answer : c)both mass and charge
14.Given the redox reaction:
Mg(s) + CuSO4(aq)--> MgSO4(aq) + Cu(s)
Which species acts as the oxidizing agent?
Answer : b) Cu2+(aq)
15.Which of the following ions is the weakest oxidizing agent?
Answer : d)Ba2+
16.Which substance is being oxidized in the following reaction?
2HCl(aq) + Zn(s) --> ZnCl2(aq) + H2(g)
Answer : c)Zn(s)
17.What is the oxidation number of Cr in K2Cr2O7?
Answer : d)+6
18.Given the following incomplete redox reaction, balance this equation in ACID solution with the set of smallest whole number coefficient:
Zn(s) + NO3-(aq) --> Zn2+(aq) + N2(g)
Identify the CORRECT statement below:
Answer : b)Zn(s) and NO3- react in a 5 to 2 mole ratio, respectively.
19.Which oxidation number is INCORRECTLY identified?
Answer : a)the oxidation number of P in phosphorus acid, H3PO3is +5
20.Which of the following is the INCORRECT statement?
Answer : c)The oxidizing agent in a redox reaction is oxidized.
21.In the reaction below, the oxidizing agent is ….
2NaCl + 2H2SO4 + MnO2 → Na2SO4 + MnSO4 + 2H2O + Cl2
Answer : a.Mn4+
22.Which substance is being reduced in the following reaction?
14H+(aq) + Cr2O72- (aq) + 6Fe2+(aq) --> 2Cr3+(aq) + 6Fe3+(aq) + 7 H2O
Answer: e)Cr2O72-
23.Given the reaction:
4 HCl(aq) + MnO2(s)--> MnCl2(aq) + 2 H2O(l) + Cl2(g)
The manganese is ….
Answer : a)reduced and its oxidation number changes from +4 to +2
24.Given the reaction:
Pb(s) + Cu2+(aq) --> Pb2+(aq) + Cu(s)
What is the reducing agent?
Answer: c)Pb(s)
25.What occurs when an atom is oxidized in a chemical reaction?
Answer : b)a loss of electrons and an increase in oxidation number
26.Given the reaction:
3 Sn4+(aq) + 2 Cr(s) --> 3 Sn2+(aq) + 2 Cr3+(aq)
Which half-reaction represents the reduction that occurs?
Answer : a)Sn4+(aq) + 2 e- --> Sn2+(aq)
27.Given the reaction:
Zn(s) + 2 HCl(aq) --> ZnCl2(aq) + H2(g)
Which substance is oxidized?
Answer : a)Zn(s)
28.A redox reaction always demonstrates the conservation of ….
Answer : c)both mass and charge
29.Given the redox reaction:
Mg(s) + CuSO4(aq)--> MgSO4(aq) + Cu(s)
Which species acts as the oxidizing agent?
Answer : b)Cu2+(aq)
30.Which of the following ions is the weakest oxidizing agent?
Answer : d)Ba2+