Assertion :- A low value of ionisation energy of the electropositive atom facilitates the formation of ionic bond.
Reason :- When the ionisation energy is less, the electropositive atom has a greater tendency to lose electron to form a cation.

Options

A. If both Assertion and Reason are CORRECT and Reason is the CORRECT explanation of the Assertion
B. If both Assertion and Reason are CORRECT but Reason is not the CORRECT explanation of the Assertion.
C. If Assertion is CORRECT but Reason is INCORRECT.
D. If Assertion is INCORRECT but Reason is CORRECT.

Answer

To solve the question, we need to analyze both the assertion and the reason provided.

### Step 1: Understand the Assertion
The assertion states: "A low value of ionization energy of the electropositive atom facilitates the formation of ionic bond."

- **Explanation**: Ionization energy is the energy required to remove an electron from an atom. Electropositive atoms, which are typically metals, have low ionization energies, meaning they can easily lose electrons to form positive ions (cations). This tendency to lose electrons is crucial for the formation of ionic bonds, where one atom donates an electron to another.

### Step 2: Understand the Reason
The reason states: "When the ionization energy is less, the electropositive atom has a greater tendency to lose an electron to form a cation."

- **Explanation**: This statement is true. A lower ionization energy indicates that less energy is required to remove an electron from the atom. Therefore, electropositive atoms with low ionization energies will readily lose electrons to form cations, which is essential for the formation of ionic bonds.

### Step 3: Determine the Relationship Between Assertion and Reason
Now we need to assess whether the reason correctly explains the assertion.

- The assertion is correct because low ionization energy does facilitate the formation of ionic bonds.
- The reason is also correct because it accurately describes why low ionization energy leads to a greater tendency to lose electrons and form cations.

### Conclusion
Both the assertion and the reason are correct, and the reason provides the correct explanation for the assertion. Therefore, the correct option is:

**Option 1**: Both assertion and reason are correct, and the reason is the correct explanation of the assertion.

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