Which of the following orbitals is empty in a carbocation?

Options

A. `sp^(2)HO`
B. `sHO's`
C. `pAO`
D. `dAO`

Explanation

To determine which orbital is empty in a carbocation, we can follow these steps:

### Step 1: Understand the Structure of a Carbocation
A carbocation is a positively charged carbon atom that has only six electrons instead of the usual eight in its valence shell. For example, in the case of the methyl carbocation (CH3+), the carbon atom has one less electron.

### Step 2: Determine the Electron Configuration of Carbon
Carbon has an atomic number of 6, meaning it has 6 electrons in its neutral state. The electron configuration of a neutral carbon atom is:
- 1s² 2s² 2p²

### Step 3: Adjust the Electron Configuration for the Carbocation
In a carbocation, one of the electrons is removed due to the positive charge. Therefore, the electron configuration for the methyl carbocation (CH3+) becomes:
- 1s² 2s² 2p¹

### Step 4: Identify the Hybridization of the Carbocation
In the methyl carbocation, the carbon atom undergoes hybridization. The 2s and two of the 2p orbitals hybridize to form three sp² hybrid orbitals. The remaining p orbital (2p) is left unhybridized.

### Step 5: Determine Which Orbitals are Filled or Empty
- The 1s orbital is fully filled (1s²).
- The 2s orbital is fully filled (2s²).
- The three sp² hybrid orbitals are filled with the bonding electrons.
- The 2p orbital (specifically the pz orbital) is empty.

### Conclusion
The empty orbital in a carbocation is the p-atomic orbital (specifically the pz orbital).

### Final Answer
The empty orbital in a carbocation is the **p-atomic orbital**.

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