Redox Reaction Exam Review Flashcards

Flashcards generated from the Redox Reaction Exam Review notes.

Which metal is most easily oxidized: Ag, Co, Cu, or Mg?

Mg

Which process involves the transfer of electrons?

oxidation-reduction

Classify the following reaction: Sn4+ + 2e– -> Sn2+

reduction reaction, because there is a decrease in oxidation number

Which half-cell reaction correctly represents oxidation?

oxidized and the oxidation number changes from 0 to + 2

In the reaction 4 Zn + 10 HNO3 -> 4 Zn(NO3)2 + NH4NO3 + 3 H2O, what happens to the zinc?

oxidized and the oxidation number changes from 0 to + 2

Which is the oxidizing agent in the reaction 2 Fe2+ + Cl2 -> 2 Fe3+ + 2 Cl–?

Cl2

What is the oxidation number of iodine in NaIO3?

+5

In which compound does chlorine have an oxidation number of +5?

HClO3

What is the oxidation state for a Mn atom?

0

What is the sum of the oxidation numbers of the atoms in the compound CO2?

0

Given the reaction: Fe(s) + Cu2+ (aq) -> Fe2+(aq) + Cu(s). Which half-reaction correctly shows the oxidation that occurs?

Fe(s) -> Fe2+(aq) + 2e–

Given the reaction: Mg + CuSO4 -> MgSO4 + Cu. Which equation represents the oxidation that takes place?

Mg -> Mg2+ + 2e–

Given the reaction: 3 Sn4+ (aq) + 2 Cr(s) -> 3 Sn2+(aq) + 2 Cr3+(aq). Which half-reaction correctly represents the reduction that occurs?

Sn4+ (aq) + 2e– -> Sn2+(aq)

Given the reaction: Mg(s) + Cl2(g) -> MgCl2(s). Which half-reaction correctly represents the reduction that occurs?

Cl2(g) + 2e– -> 2 Cl–

Which will oxidize Zn(s) to Zn2+, but will not oxidize Pb(s) to Pb2+?

Co2+

Give an example of a simple oxidation-reduction reaction that is not correctly balanced.

2 I–(aq) + Fe3+(aq) -> Fe2+ (aq) + I2(s)

Write a balanced half-reaction equation to represent the reduction of the silver ions to silver atoms in the reaction Cu(s) + 2AgNO3(aq) -> 2Ag(s) + Cu(NO3)2(aq).

Ag+(aq) + e– -> Ag(s)

Based on Table J, state why Cu(s) reacts spontaneously with Ag+(aq).

Copper is more active than silver.

State the change in oxidation state of copper in the reaction Cu(s) + 2AgNO3(aq) -> 2Ag(s) + Cu(NO3)2(aq).

from 0 to +2

Determine the oxidation state of chromium in K2CrO4.

+6

Determine the oxidation number of carbon in CO and CO2 in the reactions 2NO2(g) + 4CO(g) -> N2(g) + 4CO2(g) and 2CO(g) + O2(g) -> 2CO2(g).

+2 for carbon in CO, +4 for carbon in CO2

A voltaic cell converts chemical energy to what?

electrical energy without an external power source

In a chemical cell composed of two half-cells, how are ions allowed to flow from one half-cell to another?

a salt bridge

Which change occurs at the anode in an operating electrochemical cell?

loss of electrons

The diagram represents an electrochemical cell. What occurs when the switch is closed?

Electrons flow from Zn to Cu.

During the electrolysis of fused NaCl, which half-reaction occurs at the negative electrode?

Na+ + 1e– -> Na0

Explain, in terms of Ag atoms and Ag+(aq) ions, why the mass of the silver electrode decreases as the electrolytic cell operates.

Silver atoms lose electrons and become silver ions in the solution.

State the purpose of the power source in an electrolytic cell.

The cell requires electrical energy for the non-spontaneous reaction to occur.

Identify the cathode in an electrolytic cell plating silver onto a nickel key.

Ni(s) key / nickel

Identify the type of electrochemical cell utilizing Cu and Cu2+ ions.

voltaic cell

State one inference that can be made about the concentration of the Cu2+ ions based on the change in intensity of the color of the Cu(NO3)2(aq) solution as the voltaic cell operates.

The concentration of the Cu2+ ions decreases.