`C_(6)H_(5)C-=N` and `C_(6)H_(5)N-=C` exhibit which type of isomerism

Options

A. Position
B. Functional
C. Dextro isomerism
D. Metamerism

Explanation

To determine the type of isomerism exhibited by the compounds C₆H₅C≡N (benzonitrile) and C₆H₅N≡C (isocyanide), we can follow these steps:

### Step 1: Identify the Structures
- **C₆H₅C≡N**: This compound is known as benzonitrile, where the cyanide group (C≡N) is attached to a phenyl group (C₆H₅).
- **C₆H₅N≡C**: This compound is known as phenyl isocyanide, where the isocyanide group (N≡C) is attached to a phenyl group.

### Step 2: Analyze the Functional Groups
- In benzonitrile (C₆H₅C≡N), the functional group is a nitrile (–C≡N).
- In phenyl isocyanide (C₆H₅N≡C), the functional group is an isocyanide (–N≡C).

### Step 3: Determine the Type of Isomerism
- The two compounds have the same molecular formula (C₇H₇N) but differ in the functional groups present (nitrile vs. isocyanide).
- Since they have different functional groups, they are classified as **functional isomers**.

### Conclusion
The compounds C₆H₅C≡N and C₆H₅N≡C exhibit **functional isomerism**.

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