The stability of ionic crystal depends principally on

Options

A. high electron affinity of anion forming species
B. the lattice energy of crystal
C. low I.E of cation forming solid
D. low heat of sublimation of cation forming solid

Answer

To determine the principal factor affecting the stability of ionic crystals, we can analyze the given options step by step.

### Step 1: Understand Ionic Crystals
Ionic crystals are formed by the electrostatic attraction between positively charged cations and negatively charged anions. The stability of these structures is influenced by various factors.

### Step 2: Analyze the Options
1. **High electron affinity of anion forming species**: While high electron affinity can contribute to the formation of anions, it is not the principal factor for the stability of the entire crystal structure.

2. **Lattice energy of the crystal**: Lattice energy is the energy released when gaseous ions combine to form an ionic solid. It is a measure of the strength of the forces between the ions in an ionic solid. Higher lattice energy indicates stronger attractions between ions, leading to greater stability.

3. **Low ionization energy of cation forming solid**: Low ionization energy means that it is easier to remove an electron from the cation. However, this does not directly correlate with the stability of the ionic crystal as a whole.

4. **Low heat of sublimation of cation forming solid**: While sublimation energy is related to the stability of the solid phase, it is not the primary factor influencing the stability of ionic crystals.

### Step 3: Conclusion
Among the options provided, the **lattice energy of the crystal** is the most significant factor affecting the stability of ionic crystals. It reflects the strength of the ionic bonds formed between the cations and anions, which is crucial for the overall stability of the structure.

### Final Answer
The stability of ionic crystals depends principally on the **lattice energy of the crystal**.

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