Redox Reactions quiz #2 Flashcards
Redox Reactions quiz #2
You can tap to flip the card.
Control buttons has been changed to "navigation" mode.
1/40Skip to main content
Which one of the following reactions is a redox reaction?
A reaction where oxidation numbers of elements change is a redox reaction. In which reaction does the oxidation number of oxygen increase?
A reaction where oxygen loses electrons and its oxidation number becomes more positive. Which of the following reactions reduce(s) oxygen to form water?
A reaction where oxygen gains electrons and forms H2O, such as O2 + 4e- + 4H+ → 2H2O. Which half-reaction correctly represents reduction?
A half-reaction where a species gains electrons, such as Fe3+ + e- → Fe2+, represents reduction. What happens in redox reactions?
Electrons are transferred between reactants, resulting in changes in oxidation states. Which of the following statements about redox reactions is false?
A statement claiming that oxidation and reduction can occur independently is false; they always occur together. H2 (g) can be oxidized by which of the following?
H2 can be oxidized by a substance that acts as an oxidizing agent, such as O2 or Cl2. What happens to a reducing agent during a redox reaction?
The reducing agent is oxidized; it loses electrons. Which reaction is not an example of an oxidation–reduction reaction?
A reaction where no electron transfer or change in oxidation states occurs is not a redox reaction. Which type of equation can represent the oxidation occurring in a reaction?
An oxidation half-reaction equation, showing electron loss, represents oxidation. Which of the following is an example of oxidation?
A process where a species loses electrons, such as Fe → Fe2+ + 2e-, is an example of oxidation. What is the difference between oxidation and reduction?
Oxidation is the loss of electrons (increase in oxidation number); reduction is the gain of electrons (decrease in oxidation number). The presence of which reactant is the best indicator of an oxidation-reduction reaction?
A reactant whose oxidation state changes during the reaction indicates a redox reaction. Hydrogen peroxide can decompose in the presence of which of the following?
Hydrogen peroxide decomposes in the presence of a catalyst, often a transition metal, via a redox reaction. Which statement among a - c is false regarding the redox reactions shown?
The statement that claims oxidation and reduction can occur separately is false. Which of the following reactions are redox reactions? Check all that apply.
All reactions where electron transfer and changes in oxidation states occur are redox reactions. Which metal(s) can be oxidized with a Pb2+ solution but not with a Cd2+ solution?
Metals with reduction potentials between those of Pb2+ and Cd2+ can be oxidized by Pb2+ but not by Cd2+. Which of the following reactions result in the oxidation of sulfur? Select all that apply.
Reactions where sulfur's oxidation number increases indicate oxidation of sulfur. Which of the following acts as a reductant in the following reaction? H2(g) + Cl2(g) → 2HCl(g)
H2 acts as the reductant (reducing agent) because it is oxidized. What does the equation represent? Ca → Ca2+ + 2e-
This equation represents the oxidation of calcium. What type of battery uses the reaction Zn(s) + 2 MnO2(s) → ZnO(s) + Mn2O3(s)?
This reaction occurs in a dry cell (alkaline) battery, which is based on redox chemistry. Which substance is the reducing agent in this reaction? Cr2O7^2- + 3 HNO2 + 5 H+ → 2 Cr^3+ + 3 NO3^- + 4 H2O
HNO2 is the reducing agent because it is oxidized. Which of the following describes what takes place when iron (Fe0) is oxidized to Fe2+ ions?
Iron loses two electrons, increasing its oxidation number from 0 to +2. Whenever a molecule is oxidized, another molecule must be reduced.
True; oxidation and reduction always occur together in a redox reaction. A molecule becomes more oxidized when it __________.
A molecule becomes more oxidized when it loses electrons. A molecule becomes more oxidized when it
Loses electrons and its oxidation number increases. A molecule becomes oxidized when it __________.
Loses electrons. Oxidation and reduction always occur simultaneously and are referred to as a(n) __________ reaction.
Redox reaction. The purpose(s) of flux on an electrode is/are:
To facilitate electron transfer and prevent unwanted side reactions during redox processes. A molecule that functions as the electron donor in a redox reaction __________.
Is the reducing agent and is oxidized. Redox reactions involve the gain or loss of _____.
Electrons. When a compound is oxidized it ______ one or more electrons.
Loses. Which of the following is an oxidation-reduction reaction?
A reaction where electrons are transferred and oxidation states change. When oxygen accepts electrons, water is produced as a byproduct.
True; oxygen is reduced and forms water in many redox reactions. Which balanced equation represents a redox reaction?
An equation where oxidation numbers change, such as 2Na + Cl2 → 2NaCl. Is the reaction shown an oxidation, reduction, or neither?
If a species loses electrons, it is oxidation; if it gains electrons, it is reduction; if neither occurs, it is neither. During the electrolysis of molten NaI, what reaction occurs at the anode?
At the anode, iodide ions are oxidized to iodine: 2I- → I2 + 2e-. If a compound is reduced, what is the result?
Its oxidation number decreases as it gains electrons. A reaction that involves the transfer of electrons from one molecule to another is referred to as
A redox (oxidation-reduction) reaction. Determine whether each change represents oxidation or reduction.
If a species loses electrons, it is oxidation; if it gains electrons, it is reduction.