Frequently Asked Question

A Frost diagram is a graphical representation of the relative stability of different oxidation states of an element. Here's how to plot one:
1. Determine the oxidation states: Identify all possible oxidation states of the element you're interested in.
2. Find standard reduction potentials: Look up the standard reduction potentials (E°) for each redox couple involving the element.
3. Plot the data:

Draw a horizontal axis representing the oxidation state.

Plot each oxidation state on the axis.

For each redox couple, draw a vertical line connecting the two oxidation states involved. The length of the line represents the standard reduction potential (E°) for that couple.
4. Connect the points: Draw a line connecting the top of each vertical line to form the Frost diagram.
Key Points:

Slope: The slope of the line between two oxidation states is proportional to the standard reduction potential (E°) for the corresponding redox couple. A steeper slope indicates a more favorable reduction reaction.
Stability: The most stable oxidation state is the one with the lowest point on the Frost diagram.
Disproportionation: If a point on the Frost diagram lies above the line connecting the two points on either side of it, the species in that oxidation state is prone to disproportionation. This means it can undergo a reaction where it is both oxidized and reduced.
Example:
The Frost diagram for chlorine would show the following oxidation states: -1, 0, +1, +3, +5, +7. The vertical lines connecting these oxidation states would represent the standard reduction potentials for each redox couple.