Which of the following is NOT a characteristic of the transition elements in the series from scandium to zinc?

Options

A. The formation of coloured cations
B. The presence of at least one unpaired electron in a d-orbital of a cation
C. The ability to form complex ions
D. The possession of an oxidation state of +I

Answer

To determine which of the following is NOT a characteristic of the transition elements in the series from scandium to zinc, we will analyze each option provided.

### Step-by-Step Solution:

1. **Understanding Transition Elements**: Transition elements are defined as elements that have partially filled d orbitals. The series from scandium (Sc) to zinc (Zn) includes elements that exhibit typical characteristics of transition metals.

2. **Analyzing the Options**:
- **Option 1: Formation of colored cations**:
- Transition metals often form colored ions due to the presence of unpaired d electrons. As the d electrons can absorb certain wavelengths of light, this results in the color observed in the compounds.
- **Conclusion**: This is a characteristic of transition elements.

- **Option 2: Presence of at least one unpaired electron in a d orbital of a cation**:
- Transition metals typically have unpaired d electrons in their cations. For example, Sc (4s² 3d¹) has one unpaired electron, and Ti (4s² 3d²) has two unpaired electrons.
- **Conclusion**: This is also a characteristic of transition elements.

- **Option 3: Ability to form complex ions**:
- Transition metals can form complex ions due to their ability to coordinate with ligands. This is facilitated by their vacant d orbitals and small ionic size, allowing them to bond with various ligands.
- **Conclusion**: This is a characteristic of transition elements.

- **Option 4: Possession of an oxidation state of +1**:
- While some transition metals can exhibit a +1 oxidation state, it is not a common characteristic across the series. The most common oxidation states for these elements are +2 and +3. The +1 state is more of an exception rather than a rule.
- **Conclusion**: This is NOT a characteristic of transition elements.

3. **Final Answer**: The option that is NOT a characteristic of the transition elements in the series from scandium to zinc is **the possession of an oxidation state of +1**.