Oxidation States
Understanding the variable oxidation states exhibited by transition elements and their relative stabilities.
What is Oxidation States?
The hypothetical charge that an atom would have if all bonds to atoms of different elements were 100% ionic, with electrons assigned to the more electronegative atom.
Key points
- Explain why transition elements exhibit variable oxidation states.
- Identify the common and maximum oxidation states for transition elements.
- Describe the trend in oxidation states across a period.
- Discuss the factors affecting the stability of oxidation states.
Common exam trap
Assuming only ns electrons participate in bonding.
Definitions
- Term
Oxidation State
- Meaning
The hypothetical charge that an atom would have if all bonds to atoms of different elements were 100% ionic, with electrons assigned to the more electronegative atom.
- Term
Transition Elements
- Meaning
Elements that have incompletely filled d orbitals in their atomic or ionic state, belonging to groups 3 to 12 of the periodic table.
Learning objectives
Explain why transition elements exhibit variable oxidation states.
Identify the common and maximum oxidation states for transition elements.
Describe the trend in oxidation states across a period.
Discuss the factors affecting the stability of oxidation states.
Recognize exceptions to the general trends.
Prerequisites
Electronic configuration of transition elements
Concept of ionization energy
Understanding of atomic structure
Common mistakes
Assuming only ns electrons participate in bonding.
Forgetting that (n-1)d electrons also contribute to oxidation states.
Not considering the relative stability of different oxidation states.
Confusing the common oxidation states with the maximum possible oxidation state.
Overlooking exceptions like Sc and Zn.
Keywords
Transition elements
Oxidation states
Variable oxidation states
Electronic configuration
Ionization energy
Sublimation enthalpy
Hydration enthalpy
First transition series
Practice preview
The most stable oxidation state of Iron (Fe) is:…
easy
The variable oxidation states of transition metals are due to the involvement of:…
medium
Which of the following statements about the oxidation states of transition metals is INCORRECT?…
medium