How many 'sp' hybrid orbital are there in allene `C_(3)H_(4)` ?

Explanation

To determine how many 'sp' hybrid orbitals are present in allene (C₃H₄), we can follow these steps:

### Step 1: Identify the Carbon Atoms in Allene
Allene consists of three carbon atoms (C₃) and four hydrogen atoms (H₄). The structure of allene can be represented as H₂C=C=CH₂, where the central carbon is double-bonded to both terminal carbons.

### Step 2: Determine the Hybridization of Each Carbon Atom
In allene, the terminal carbon atoms (the first and third carbon) are involved in two single bonds with hydrogen and one double bond with the central carbon. The central carbon atom is involved in two double bonds (one with each terminal carbon).

- The terminal carbon atoms (C1 and C3) are **sp² hybridized** because they form three sigma bonds (two with hydrogen and one with the central carbon).
- The central carbon atom (C2) is **sp hybridized** because it forms two pi bonds (one with each terminal carbon) and has no hydrogen atoms attached.

### Step 3: Count the 'sp' Hybrid Orbitals
Since only the central carbon atom (C2) is sp hybridized, we will count the number of sp hybrid orbitals:

- **C2 (central carbon)**: 2 sp hybrid orbitals (one for each double bond with the terminal carbon atoms).

### Conclusion
In total, there is **1 sp hybrid orbital** from the central carbon atom in allene.

### Final Answer
**There is 1 'sp' hybrid orbital in allene (C₃H₄).**

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