The answer to each of the following questions is a non- negative integer.
The ratio of number of lone pairs on the central atom of CIF3, and `XeF_4` is……

Answer

To find the ratio of the number of lone pairs on the central atom of ClF3 (Chlorine Trifluoride) and XeF4 (Xenon Tetrafluoride), we will follow these steps:

### Step-by-Step Solution:

1. **Identify the central atom in ClF3:**
- In ClF3, the central atom is chlorine (Cl).

2. **Determine the number of valence electrons for Cl:**
- Chlorine has 7 valence electrons.

3. **Count the number of fluorine atoms bonded to Cl:**
- ClF3 has 3 fluorine (F) atoms bonded to chlorine.

4. **Calculate the number of bonding electrons:**
- Each bond with fluorine uses 1 electron. Therefore, 3 bonds use 3 electrons.
- Total bonding electrons = 3 (for 3 Cl-F bonds).

5. **Calculate the number of lone pairs on Cl in ClF3:**
- Remaining electrons = Total valence electrons - Bonding electrons
- Remaining electrons = 7 - 3 = 4 electrons.
- Lone pairs = Remaining electrons / 2 = 4 / 2 = 2 lone pairs.

6. **Identify the central atom in XeF4:**
- In XeF4, the central atom is xenon (Xe).

7. **Determine the number of valence electrons for Xe:**
- Xenon has 8 valence electrons.

8. **Count the number of fluorine atoms bonded to Xe:**
- XeF4 has 4 fluorine (F) atoms bonded to xenon.

9. **Calculate the number of bonding electrons:**
- Each bond with fluorine uses 1 electron. Therefore, 4 bonds use 4 electrons.
- Total bonding electrons = 4 (for 4 Xe-F bonds).

10. **Calculate the number of lone pairs on Xe in XeF4:**
- Remaining electrons = Total valence electrons - Bonding electrons
- Remaining electrons = 8 - 4 = 4 electrons.
- Lone pairs = Remaining electrons / 2 = 4 / 2 = 2 lone pairs.

11. **Calculate the ratio of lone pairs:**
- Lone pairs on ClF3 = 2
- Lone pairs on XeF4 = 2
- Ratio = Lone pairs on ClF3 / Lone pairs on XeF4 = 2 / 2 = 1.

12. **Final Answer:**
- The ratio of the number of lone pairs on the central atom of ClF3 to XeF4 is 1.