Number of `p pi-d pi` bonds present in `XeO_(4)` are

Explanation

To determine the number of `p pi-d pi` bonds present in `XeO4`, we can follow these steps:

### Step 1: Identify the central atom and its valence electrons
- The central atom in `XeO4` is Xenon (Xe).
- Xenon has a total of 8 valence electrons (from the electronic configuration: 5s² 5p⁶).

**Hint:** Remember that the number of valence electrons is crucial for understanding bonding.

### Step 2: Determine the bonding with oxygen
- In `XeO4`, Xenon forms four sigma bonds with four oxygen atoms. Each oxygen atom forms a sigma bond with Xenon by sharing one of its own electrons.

**Hint:** Sigma bonds are formed by the head-on overlap of orbitals.

### Step 3: Analyze the hybridization of Xenon
- Since Xenon forms four sigma bonds and has no lone pairs, the steric number is 4. This indicates that the hybridization of Xenon is `sp³`.

**Hint:** The steric number helps determine the hybridization state of the central atom.

### Step 4: Consider the excited state of Xenon
- In the excited state, one of the 5s electrons is promoted to the 5d orbital. Thus, the excited state electronic configuration can be represented as: 5s¹ 5p³ 5d¹.

**Hint:** Excited state configurations are important for understanding how bonding occurs in compounds.

### Step 5: Determine the formation of `p pi-d pi` bonds
- The `p pi-d pi` bonds are formed when the 2p orbitals of the oxygen atoms overlap with the 5d orbitals of Xenon. Since there are four oxygen atoms, each contributing a 2p orbital, there will be four `p pi-d pi` bonds formed.

**Hint:** The nature of pi bonds is determined by the type of orbitals involved in the overlap.

### Conclusion
- Therefore, the total number of `p pi-d pi` bonds present in `XeO4` is **4**.

**Final Answer:** 4 `p pi-d pi` bonds.

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