Read the following statements for the formation of ionic bond :
(a) small cation, large anion
(b) low IP of cation, high EA of anion
(c) large cation, small anion and less charge
(d) less lattice energy
Which of the following groups of statements is correct ?

Question

Accepted Answer

To understand why Option 3 is the correct answer, we need to analyze the statements related to the formation of ionic bonds and evaluate them based on established chemical principles.

### Explanation for Option 3: (b) and (c)

1. **Statement (b): Low IP of cation, high EA of anion**
   - **Ionization Potential (IP)**: This is the energy required to remove an electron from an atom. A low IP for the cation means it can easily lose an electron to form a positive ion, which is a key step in forming an ionic bond.
   - **Electron Affinity (EA)**: This is the energy change when an electron is added to an atom. A high EA for the anion indicates that the atom readily gains an electron to form a negative ion. This is crucial for the formation of an ionic bond as it stabilizes the anion.
   - Therefore, a low IP for the cation and a high EA for the anion are conducive to the formation of ionic bonds, making statement (b) correct.

2. **Statement (c): Large cation, small anion and less charge**
   - **Large Cation and Small Anion**: A large cation and a small anion can lead to a strong electrostatic attraction, which is essential for the stability of an ionic bond. The size difference helps in maximizing the attraction between the oppositely charged ions.
   - **Less Charge**: While typically higher charges can lead to stronger ionic bonds, in some cases, less charge can reduce repulsion between ions in a lattice, contributing to stability in certain ionic compounds.
   - Thus, statement (c) is also correct in describing conditions favorable for ionic bond formation.

### Explanation for Why Other Options are Incorrect

1. **Option 1: (a) and (d)**
   - **Statement (a): Small cation, large anion**
     - This is generally less favorable for ionic bond formation because a small cation and large anion can lead to weaker electrostatic interactions compared to a large cation and small anion.
   - **Statement (d): Less lattice energy**
     - Lattice energy is the energy released when ions come together to form a lattice. Higher lattice energy typically indicates a stronger ionic bond. Therefore, less lattice energy is not favorable for strong ionic bond formation.

2. **Option 2: (b), (c) and (d)**
   - While (b) and (c) are correct, as explained, statement (d) is incorrect for the reasons mentioned above.

3. **Option 4: (a) and (b)**
   - While statement (b) is correct, statement (a) is not favorable for the reasons previously discussed.

In conclusion, Option 3, which includes statements (b) and (c), correctly describes the conditions that are conducive to the formation of ionic bonds, making it the correct choice.