Which of the following is a ferroelectric compound?

Options

A. `BaTiO_(3)`
B. `K_(4)[Fe(CN)_(6)]`
C. `Pb_(2)O_(3)`
D. None of these

Answer

To determine which of the given compounds is a ferroelectric compound, we need to understand the characteristics of ferroelectric materials and analyze the options provided.

### Step-by-Step Solution:

1. **Definition of Ferroelectric Compounds**:
- Ferroelectric compounds exhibit spontaneous electric polarization that can be reversed by the application of an external electric field. This means that these materials can maintain a permanent electric dipole moment even in the absence of an external electric field.

2. **Analyzing the Options**:
- The options given are:
- a) BaTiO3
- b) K4Fe(CN)6
- c) PbTiO3
- d) None of these

3. **Identifying Ferroelectric Compounds**:
- **BaTiO3 (Barium Titanate)**:
- BaTiO3 is known to be a classic ferroelectric material. It exhibits spontaneous polarization and can have its polarization reversed by an external electric field. It crystallizes in a perovskite structure, which contributes to its ferroelectric properties.
- **K4Fe(CN)6 (Potassium Ferrocyanide)**:
- This compound is a coordination compound and does not exhibit ferroelectric properties.
- **PbTiO3 (Lead Titanate)**:
- PbTiO3 is also a well-known ferroelectric material, similar to BaTiO3, and exhibits spontaneous polarization.
- **None of these**:
- This option suggests that none of the compounds listed are ferroelectric, which is incorrect since both BaTiO3 and PbTiO3 are ferroelectric.

4. **Conclusion**:
- Among the options provided, both **BaTiO3** and **PbTiO3** are ferroelectric compounds. However, if we are to choose one based on the context of the question, **BaTiO3** is often highlighted as a classic example of a ferroelectric material.

### Final Answer:
- The ferroelectric compound from the options given is **BaTiO3**.