complete the following:
`C_(6)H_(5)COOHoverset(conc. HNO_(3)+ conc. H_(2)SO_(4)+heat)rarr`

Explanation

To complete the reaction of benzoic acid (C₆H₅COOH) when treated with concentrated nitric acid (HNO₃), concentrated sulfuric acid (H₂SO₄), and heat, we follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**: The starting material is benzoic acid (C₆H₅COOH). The reagents used are concentrated nitric acid (HNO₃) and concentrated sulfuric acid (H₂SO₄), along with heat.

2. **Understand the Reaction Type**: The reaction is a nitration reaction, which involves the introduction of a nitro group (NO₂) into the aromatic ring of benzoic acid.

3. **Determine the Directing Effects**: The carboxylic acid group (-COOH) is an electron-withdrawing group. This means it will direct incoming electrophiles (like the nitronium ion, NO₂⁺) to the meta position of the aromatic ring.

4. **Identify the Positions on the Ring**: In the benzene ring of benzoic acid:
- The ortho position is adjacent to the -COOH group.
- The meta position is one carbon away from the -COOH group.
- The para position is directly opposite the -COOH group.

5. **Predict the Product**: Since the -COOH group is meta-directing, the nitro group will be added at the meta position relative to the carboxylic acid group. The product formed will be 3-nitrobenzoic acid (or meta-nitrobenzoic acid).

6. **Write the Balanced Equation**:
\[ C_6H_5COOH + HNO_3 \xrightarrow{H_2SO_4, \text{heat}} C_6H_4(NO_2)COOH + H_2O \]
This indicates that benzoic acid reacts with nitric acid to form meta-nitrobenzoic acid and water.

### Final Answer:
The complete reaction is:
\[ C_6H_5COOH \overset{conc. HNO_3 + conc. H_2SO_4 + heat}{\rightarrow} C_6H_4(NO_2)COOH + H_2O \]
where \( C_6H_4(NO_2)COOH \) is meta-nitrobenzoic acid.