IUPAC name of `CH_3 -C -= CH` is

Options

A. propane
B. propene
C. propanol
D. propyne

Explanation

To determine the IUPAC name of the compound `CH3-C≡CH`, we can follow these steps:

### Step 1: Identify the Longest Carbon Chain
The first step in naming any organic compound is to identify the longest continuous carbon chain. In this case, the compound has three carbon atoms connected in a straight chain.

### Step 2: Number the Carbon Atoms
Next, we need to number the carbon atoms in the chain. We will start numbering from the end of the chain that gives the lowest number to the functional group (in this case, the triple bond). The numbering will be as follows:
- Carbon 1: CH3
- Carbon 2: C (part of the triple bond)
- Carbon 3: CH

### Step 3: Identify the Functional Group
The compound contains a triple bond between Carbon 2 and Carbon 3. In IUPAC nomenclature, a triple bond is indicated by the suffix "-yne".

### Step 4: Determine the Prefix
Since there are three carbon atoms in the longest chain, we use the prefix "prop-" (from propane).

### Step 5: Combine the Elements
Now, we combine the prefix, the position of the triple bond, and the suffix:
- The longest chain has 3 carbons: "prop"
- The triple bond starts at Carbon 1: "1"
- The suffix for a triple bond: "-yne"

Thus, the IUPAC name for `CH3-C≡CH` is **prop-1-yne**. However, since the triple bond is at the first carbon, we can also simply refer to it as **propyne**.

### Final Answer
The IUPAC name of `CH3-C≡CH` is **propyne**.

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