Hydrated `Cu^(2+)` ions absorb light of ..... colour and transmit light of ....... colour

Options

A. red and blue
B. green and purple
C. purple and red
D. blue and red

Answer

To solve the question regarding the color absorption and transmission of hydrated `Cu^(2+)` ions, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Compound**:
We are dealing with hydrated `Cu^(2+)` ions, which typically refer to copper(II) sulfate pentahydrate, represented as `CuSO4·5H2O`.

**Hint**: Remember that the presence of water molecules in the compound affects its color.

2. **Determine the Color of Hydrated `Cu^(2+)` Ions**:
The hydrated `Cu^(2+)` ions are known to exhibit a blue color due to the presence of water molecules and the coordination of water around the copper ion.

**Hint**: Look up the common colors associated with transition metal complexes.

3. **Understand Light Absorption and Transmission**:
When a substance absorbs certain wavelengths of light, it transmits the complementary color. For `Cu^(2+)` ions, they absorb light in the red region of the spectrum.

**Hint**: Use the color wheel to determine complementary colors; for blue, the complementary color is red.

4. **Conclusion**:
Therefore, hydrated `Cu^(2+)` ions absorb red light and transmit blue light.

**Final Answer**: Hydrated `Cu^(2+)` ions absorb light of red color and transmit light of blue color.

### Summary of the Solution:
- **Absorbed Color**: Red
- **Transmitted Color**: Blue