The IUPAC name of `CH_3COOH` is

Options

A. methanal
B. ethanoic acid
C. methanol
D. methanoic acid

Explanation

To determine the IUPAC name of the compound `CH₃COOH`, we can follow these steps:

### Step 1: Identify the Structure
The molecular formula `CH₃COOH` represents a compound that consists of two carbon atoms, one of which is part of a carboxylic acid functional group (COOH). The structure can be drawn as follows:

```
H O
| ||
H--C--C--O--H
|
H
```

### Step 2: Count the Carbon Atoms
In the structure, we can see that there are two carbon atoms:
1. The first carbon (C1) is part of the methyl group (CH₃).
2. The second carbon (C2) is part of the carboxylic acid group (COOH).

### Step 3: Determine the Longest Carbon Chain
The longest carbon chain in this compound consists of two carbon atoms. Therefore, we will use the prefix "eth-" for two carbon atoms.

### Step 4: Identify the Functional Group
The presence of the carboxylic acid group (COOH) indicates that this compound is an acid. The suffix for carboxylic acids is "-oic acid".

### Step 5: Combine Prefix and Suffix
Since we have two carbon atoms, we use the prefix "eth-" and combine it with the suffix "-oic acid".

### Step 6: Final Name
Putting it all together, we remove the "e" from "ethane" (as per IUPAC nomenclature rules when combining with a suffix that starts with a vowel) and add the suffix "-oic acid". Thus, the final IUPAC name of `CH₃COOH` is **ethanoic acid**.

### Summary
The IUPAC name of `CH₃COOH` is **ethanoic acid**.

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