Latimer Diagram Flashcards
What is a Latimer diagram?
A Latimer diagram is a graphical representation of reduction potentials of various oxidation states of a species.
True or False: Latimer diagrams display the stability of different oxidation states.
True
What does the vertical axis of a Latimer diagram represent?
The vertical axis represents the reduction potential (E°) values.
In a Latimer diagram, what is indicated by a downward arrow?
A downward arrow indicates a reduction process.
What is the primary use of a Latimer diagram?
The primary use is to visualize and compare the reduction potentials of different oxidation states.
Fill in the blank: The highest oxidation state in a Latimer diagram is typically the _____ state.
most oxidized
Which element is commonly represented in Latimer diagrams for oxygen?
Oxygen (O)
What do the horizontal lines in a Latimer diagram represent?
The horizontal lines represent the different oxidation states of the species.
True or False: Latimer diagrams can only be used for simple ions.
False
What is the relationship between reduction potential and stability in a Latimer diagram?
Higher reduction potentials indicate greater stability of the reduced form.
What is the reduction potential for the reaction O2 + 4H+ + 4e- → 2H2O?
The reduction potential is +1.23 V.
Multiple Choice: Which oxidation state of oxygen is the most reduced in a Latimer diagram? a) O2, b) H2O, c) O2-
b) H2O
What does a positive reduction potential indicate?
It indicates a favorable reduction reaction.
Fill in the blank: In a Latimer diagram, the lower the oxidation state, the _____ the reduction potential.
higher
What is the significance of the transition between oxidation states in a Latimer diagram?
It shows the thermodynamic feasibility of the reduction reaction.
True or False: Latimer diagrams can help predict reaction pathways.
True
What is the common oxidation state of molecular oxygen in a Latimer diagram?
0 (zero)
Multiple Choice: Which of the following is NOT typically represented in a Latimer diagram? a) Oxidation states, b) Temperature, c) Reduction potentials
b) Temperature
What does the term ‘reduction’ refer to in the context of a Latimer diagram?
Reduction refers to the gain of electrons by a species.
Fill in the blank: A Latimer diagram can also be referred to as a _____ potential diagram.
reduction
What is the relationship between the oxidation state and reduction potential for a given element in a Latimer diagram?
As the oxidation state decreases, the reduction potential generally increases.
True or False: Latimer diagrams can be used for both organic and inorganic compounds.
True
What is the function of the slashes in a Latimer diagram?
Slashes indicate the electron transfer associated with the reduction process.
Multiple Choice: In a Latimer diagram, the species with the highest reduction potential is usually the: a) most oxidized, b) most reduced, c) least stable
a) most oxidized
What does the term ‘oxidation state’ refer to?
The oxidation state refers to the charge of an atom in a compound, indicating its degree of oxidation or reduction.
Fill in the blank: Latimer diagrams are particularly useful for understanding the _____ of redox reactions.
thermodynamics
What is the reduction potential for the half-reaction H2O + 2e- → H2 + 2OH-?
The reduction potential is -0.83 V.
True or False: The reduction potential values in a Latimer diagram are always positive.
False
What does a Latimer diagram help to determine about an element’s oxidation states?
It helps to determine the stability and likelihood of each oxidation state.
What is the oxidized form of element X in a redox couple?
X(N)
X(N) represents the oxidized form of X in the redox couple.
What does AG° represent in the context of redox reactions?
Gibbs free energy change
AG° is defined as the change in Gibbs free energy for a reaction.
What is the relationship between AG° and NE°?
AG° = -NE°F
This equation shows that Gibbs free energy change is related to the number of electrons transferred and the Faraday constant.
What is the purpose of a Frost diagram?
To plot NE° against oxidation number N
A Frost diagram helps visualize the relationship between the standard reduction potential and oxidation states of an element.
What is the y-axis of a Frost diagram?
NE°
NE° is plotted on the y-axis (abscissa) of the Frost diagram.
What is plotted on the x-axis of a Frost diagram?
Oxidation number N
The oxidation number N is plotted on the x-axis (ordinate) of the Frost diagram.
What does E° represent in electrochemistry?
Standard reduction potential
E° indicates the tendency of a species to be reduced under standard conditions.
What is the meaning of zero oxidation number (0) for element X?
Elemental state of X
The zero oxidation number signifies that the element is in its elemental form.
What is the plot of NE° versus N equivalent to?
Plot of -AG° versus N
The relationship shows that as NE° increases, the Gibbs free energy change decreases.
When multiple species of an element exist in different oxidation states, what needs to be determined?
E° value for each species
Each species involved in reduction half-reactions must have its E° value determined for accurate plotting.
What is the standard reduction potential E° for the oxidized form of X?
+0.70 V
This value indicates the standard reduction potential for the oxidized form of X.
What is the standard reduction potential E° for the reduced form of X?
+1.76 V
This value indicates the standard reduction potential for the reduced form of X.
What is determined for each species involved in a reduction half reaction in relation to E⁰ values?
E⁰ value for each species
This is essential for plotting the Frost diagram.
What is plotted against oxidation number (N) to obtain a Frost diagram?
NE⁰ values
The points for each species are joined to create the diagram.
In a Frost diagram, what does the species occupying the lowest position represent?
The most stable oxidation state of the element
This is illustrated in the Frost diagram figures.
Which species in the Frost diagram is likely to undergo reduction?
The species represented by point D
It has a higher E⁰ value compared to others.
Which species is liable to undergo oxidation in the Frost diagram?
The species represented by point B
It has a lower E⁰ value compared to others.
What is the oxidation state of N in the molecule N₂O₄?
+4
This is relevant for understanding the stability of the species.
What occurs to the N₂O₄ molecule in the Frost diagram of nitrogen?
It undergoes disproportionation into NO₂ and NO₃⁻
This indicates instability with respect to the line joining these species.
What does the Frost diagram indicate about the stability of N₂O₄?
N₂O₄ is unstable with respect to disproportionation
This is due to its position above the line joining NO₂ and NO₃⁻.
What are the oxidation states of the species involved in the disproportionation of N₂O₄?
- NO₂ (N=+3)
- NO₃⁻ (N=+5)
This shows the range of oxidation states in the reaction.
Fill in the blank: In the Frost diagram, the couple corresponding to points C and D have _______ E⁰ values than the couple corresponding to points B and C.
higher
This comparison helps determine which species undergoes reduction or oxidation.
True or False: The Frost diagram for nitrogen shows that HNO₃ and HNO₂ have the same oxidation number.
False
HNO₃ has N in the +5 state while HNO₂ has N in the +3 state.
