The `IUPAC` name of `CH_(2)=CHCN` is:

Options

A. Cyanoethene
B. Vinyl cyanide
C. Ethenenitrile
D. Prop-2-ene nitrile

Answer

To determine the IUPAC name of the compound CH₂=CHCN, we can follow these steps:

### Step 1: Identify the longest carbon chain
The given structure has three carbon atoms. The longest carbon chain consists of three carbon atoms, which can be represented as follows:
- C1: CH₂
- C2: CH
- C3: CN (where the carbon is attached to the nitrogen)

### Step 2: Number the carbon chain
We need to number the carbon chain in such a way that the functional groups get the lowest possible numbers. In this case, we start numbering from the end of the chain closest to the double bond:
- C1: CH₂ (1)
- C2: CH (2)
- C3: CN (3)

### Step 3: Identify the functional groups
In this compound, we have:
- A double bond between C1 and C2 (alkene)
- A nitrile group (CN) attached to C3

### Step 4: Assign the correct suffix and prefix
According to IUPAC nomenclature:
- The longest carbon chain (3 carbons) is called "prop".
- The presence of a double bond at position 2 indicates that we use the suffix "2-ene".
- The nitrile group is a functional group that we denote as "nitrile".

### Step 5: Combine the elements to form the IUPAC name
Putting it all together, we have:
- The base name is "prop" for the three carbon atoms.
- The double bond is at position 2, so we write "prop-2-ene".
- The nitrile group is attached to the first carbon, so we write "1-nitrile".

Thus, the complete IUPAC name is **prop-2-ene-1-nitrile**.

### Final Answer:
The IUPAC name of CH₂=CHCN is **prop-2-ene-1-nitrile**.

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