The conversion of primary aromtatic amines in to diazonium salts is known as

Explanation

**Step-by-Step Solution:**

1. **Understanding the Reaction**: The conversion of primary aromatic amines into diazonium salts involves a specific chemical reaction where the amine group (-NH2) of the aromatic compound is transformed into a diazonium group (-N2+).

2. **Identifying the Reactants**: The primary aromatic amine, such as aniline (C6H5NH2), is the starting material. This amine will react with sodium nitrite (NaNO2) in the presence of a mild acid.

3. **Choosing the Acid**: A mild acid such as hydrochloric acid (HCl) is typically used in this reaction. The acid helps to protonate the nitrite ion, facilitating the formation of the diazonium salt.

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