Which one of the following is an ingredient of Pthalic acid manufacture by catalytic oxidation

Options

A. Benzene
B. Salicyclic acid
C. Anthranilic acid
D. naphthalene

Explanation

To solve the question regarding the ingredient used in the manufacture of phthalic acid by catalytic oxidation, we can follow these steps:

### Step 1: Understand the Structure of Phthalic Acid
Phthalic acid is a dicarboxylic acid with the chemical formula C8H6O4. It consists of two carboxyl (-COOH) groups attached to a benzene ring.

### Step 2: Identify the Starting Material for Catalytic Oxidation
The catalytic oxidation process typically starts with an aromatic compound. In the case of phthalic acid, the most common precursor is naphthalene or ortho-xylene.

### Step 3: Consider the Oxidation Process
During the catalytic oxidation, the aromatic compound undergoes oxidation, which involves the addition of oxygen and the removal of hydrogen. This process ultimately leads to the formation of carboxylic acid groups on the aromatic ring.

### Step 4: Determine the Correct Ingredient
Among the options provided, we need to identify which compound can be oxidized to yield phthalic acid. The correct ingredient is typically ortho-xylene, as it can be oxidized to form phthalic acid.

### Step 5: Conclusion
Thus, the ingredient used in the manufacture of phthalic acid by catalytic oxidation is ortho-xylene.

### Final Answer
The correct ingredient for the manufacture of phthalic acid by catalytic oxidation is **ortho-xylene**.

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