Which block elements are called transition elements ?

Options

A. s - block
B. p - block
C. d - block
D. f - block

Explanation

**Step-by-Step Solution:**

1. **Understanding the Periodic Table:**
- The modern periodic table is organized into groups and periods. Groups are the vertical columns, and periods are the horizontal rows.

2. **Identifying the Blocks:**
- The elements in the periodic table are classified into four blocks based on their electron configurations:
- **s-block:** Groups 1 and 2 (alkali and alkaline earth metals).
- **p-block:** Groups 13 to 18 (includes non-metals and metalloids).
- **d-block:** Groups 3 to 12 (transition metals).
- **f-block:** Lanthanides and actinides, typically placed below the main body of the periodic table.

3. **Defining Transition Elements:**
- Transition elements are specifically the d-block elements, which are located in groups 3 to 12 of the periodic table.

4. **Characteristics of Transition Elements:**
- Transition elements are known for their ability to form variable oxidation states, complex ions, and colored compounds. They are also good conductors of electricity and heat.

5. **Conclusion:**
- Therefore, the elements that are classified as transition elements are the d-block elements of the periodic table.

**Final Answer:**
The transition elements are the d-block elements, which are located in groups 3 to 12 of the modern periodic table.

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