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 of 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 in the question.

### Step-by-Step Solution:

1. **Understanding Transition Elements**:
Transition elements, also known as d-block elements, are found in the periodic table from scandium (Sc) to zinc (Zn). They are characterized by the presence of d-orbitals that are being filled with electrons.

2. **Analyzing Option 1: Formation of Colored Cations**:
- Transition elements often form colored cations due to the presence of unpaired electrons in their d-orbitals.
- **Conclusion**: This statement is TRUE for transition elements.

3. **Analyzing Option 2: Presence of At Least One Unpaired Electron in d-Orbital of a Cation**:
- Transition metals typically have unpaired electrons in their d-orbitals, which is a characteristic feature of these elements.
- **Conclusion**: This statement is also TRUE for transition elements.

4. **Analyzing Option 3: Ability to Form Complex Ions**:
- Transition metals have the ability to form complex ions, often due to their vacant d-orbitals and small ionic size, which allows them to coordinate with ligands.
- **Conclusion**: This statement is TRUE for transition elements.

5. **Analyzing Option 4: Possession of an Oxidation State of Plus 1**:
- While transition metals can exhibit various oxidation states, the common oxidation states for the first transition series (from Sc to Zn) are +2 and +3. The +1 oxidation state is not typical for most of these elements, with exceptions like copper (Cu) and chromium (Cr).
- **Conclusion**: This statement is NOT a characteristic of the transition elements from scandium to zinc.

### Final Answer:
The option that is NOT a characteristic of the transition elements in the series from scandium to zinc is **Option 4: Possession of an oxidation state of plus 1**.

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