The IUPAC name of the phthalic acid-

Options

A. Benzene-1,2-dicarboxylic acid
B. Benzene-1,4-dioic acid
C. Cyclo-1,3,5-trien-1,2-diolic acid
D. Benzene-1,3-dicarboxylic acid

Answer

To determine the IUPAC name of phthalic acid, follow these steps:

### Step 1: Identify the Structure
Phthalic acid is derived from benzene and contains two carboxylic acid groups (-COOH) attached to the benzene ring.

### Step 2: Determine the Position of the Carboxylic Groups
In phthalic acid, the two carboxylic acid groups are located at the 1 and 2 positions of the benzene ring. This means they are adjacent to each other.

### Step 3: Name the Benzene Ring
The base name of the compound is derived from benzene, as it is the parent hydrocarbon.

### Step 4: Indicate the Presence of Two Carboxylic Acid Groups
Since there are two carboxylic acid groups, we use the prefix "di-" to indicate this.

### Step 5: Combine the Information
Putting all the information together, we name the compound as "Benzene-1,2-dicarboxylic acid".

### Final Answer
The IUPAC name of phthalic acid is **Benzene-1,2-dicarboxylic acid**.

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