Name of `CH_3CHO` in IUPAC system is

Options

A. acetaldehyde
B. methyl aldehyde
C. formyl methane
D. ethanal

Explanation

To determine the IUPAC name of the compound CH₃CHO, we can follow these steps:

### Step 1: Identify the Structure
The molecular formula CH₃CHO indicates that there are two carbon atoms. The structure can be drawn as follows:
- The first carbon (C1) is connected to three hydrogen atoms (H) and is bonded to the second carbon (C2).
- The second carbon (C2) is connected to one hydrogen atom and has a double bond with an oxygen atom (O), which indicates the presence of an aldehyde functional group.

### Step 2: Determine the Longest Carbon Chain
In this case, the longest carbon chain consists of two carbon atoms. This is important for naming the compound.

### Step 3: Assign the Prefix
For a two-carbon chain, the prefix is "eth-". This indicates that there are two carbon atoms in the main chain.

### Step 4: Identify the Functional Group
The presence of the aldehyde group (-CHO) is crucial for naming. Aldehydes are characterized by the functional group at the end of the carbon chain.

### Step 5: Assign the Suffix
The suffix for aldehydes is "-al". Therefore, we combine the prefix and the suffix.

### Step 6: Combine the Prefix and Suffix
Putting it all together, we have:
- Prefix: "eth-"
- Suffix: "-al"

Thus, the IUPAC name of CH₃CHO is **ethanal**.

### Final Answer
The IUPAC name of CH₃CHO is **ethanal**.

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