What is the correct IUPAC name of acetonitrile ?

Options

A. Ethanenitrile
B. Cyanomethane
C. Methanenitrile
D. Cyanoethane

Explanation

To determine the correct IUPAC name of acetonitrile, we can follow these steps:

### Step 1: Identify the Structure
Acetonitrile has the molecular formula CH₃CN. It consists of a methyl group (CH₃-) attached to a nitrile group (-C≡N).

### Step 2: Select the Parent Chain
In IUPAC nomenclature, we need to identify the longest carbon chain that includes the functional group. In the case of acetonitrile, the longest chain consists of two carbon atoms (the methyl group and the carbon in the nitrile group).

### Step 3: Number the Carbon Chain
We need to number the carbon chain to give the functional group the lowest possible number. In this case, we can number the carbon atoms as follows:
- Carbon 1: CH₃ (methyl group)
- Carbon 2: C≡N (nitrile group)

### Step 4: Determine the Name
The base name for a two-carbon alkane is "ethane." Since we have a nitrile functional group, we modify the name to reflect this. The suffix for a nitrile is "-nitrile." Therefore, we combine the base name and the functional group to get "ethanenitrile."

### Conclusion
The correct IUPAC name for acetonitrile is **ethanenitrile**.

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