Colour of transition metal ions are due to absorption of some wavelength. This results in

Options

A. 1. d-s transition
B. 2. s-s transition
C. 3. s-d transition
D. 4. d-d transition

Answer

**Step-by-Step Solution:**

1. **Understanding Transition Metals:**
Transition metals are elements that have partially filled d orbitals. These include elements from groups 3 to 12 of the periodic table.

2. **Color of Transition Metal Ions:**
The color of transition metal ions arises due to their ability to absorb certain wavelengths of light. This absorption occurs when electrons in the d orbitals are excited from a lower energy level to a higher energy level.

3. **d-d Transitions:**
The specific process responsible for the color of these ions is known as d-d transitions. In this process, an electron in a lower energy d orbital absorbs energy (in the form of light) and jumps to a higher energy d orbital.

4. **Emission of Light:**
When the excited electron returns to its original lower energy state, it releases energy in the form of light. The color observed is related to the specific wavelength of light that is emitted. The wavelengths absorbed correspond to the complementary color of the emitted light.

5. **Conclusion:**
Therefore, the color of transition metal ions is primarily due to d-d transitions, where electrons transition between different d orbitals upon absorbing energy.

**Final Answer:**
The color of transition metal ions is due to d-d transitions, which result in the absorption of specific wavelengths of light.

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