The number of `pi` electrons present in phenanthrecene

Options

A. 10
B. 14
C. 12
D. 16

Answer

To determine the number of π (pi) electrons present in phenanthrene, we can follow these steps:

### Step 1: Understand the Structure of Phenanthrene
Phenanthrene is an aromatic hydrocarbon that consists of three fused benzene rings. Each benzene ring contributes to the overall π electron count.

### Step 2: Identify the π Electrons in a Benzene Ring
Each benzene ring has a total of 6 π electrons. In benzene, these π electrons are delocalized over the ring structure, contributing to its aromatic stability.

### Step 3: Count the Total Number of Benzene Rings in Phenanthrene
Phenanthrene is made up of three fused benzene rings.

### Step 4: Calculate the Total Number of π Electrons
Since each benzene ring contributes 6 π electrons, we can calculate the total number of π electrons in phenanthrene as follows:
- Total π electrons = Number of benzene rings × π electrons per benzene ring
- Total π electrons = 3 rings × 6 π electrons/ring = 18 π electrons

### Conclusion
Therefore, the total number of π electrons present in phenanthrene is **18**.

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