Valence bond theory explains the colour of the coordination compounds .

Answer

To determine whether the statement "Valence bond theory explains the colour of the coordination compounds" is true or false, we can follow these steps:

### Step 1: Understand the Theories
- **Valence Bond Theory (VBT)**: This theory focuses on the formation of chemical bonds through the overlap of atomic orbitals. It explains how atoms bond but does not specifically address the color of coordination compounds.
- **Crystal Field Theory (CFT)**: This theory explains the behavior of electrons in coordination compounds, particularly how they are affected by the electric fields produced by surrounding ligands. CFT is crucial for understanding the color and magnetism of these compounds.

### Step 2: Analyze the Role of CFT
- CFT explains the splitting of d-orbitals in transition metal complexes when ligands approach the metal ion. The difference in energy between the split d-orbitals corresponds to the energy of visible light, which is why these complexes can absorb certain wavelengths of light and appear colored.

### Step 3: Relate to the Statement
- Since VBT does not explain the color of coordination compounds and it is CFT that provides this explanation, we can conclude that the statement is incorrect.

### Conclusion
- Therefore, the statement "Valence bond theory explains the colour of the coordination compounds" is **false**.

### Final Answer
**False** - Valence bond theory does not explain the color of coordination compounds; this is explained by crystal field theory.

---