How many anions will give colourles acid vapour/ gas with conc. `H_(2)SO_(4)` on reaction with following gives anions?
`CH_(3)COO^(-) ,Cl^(-),Br^(-),S^(2-),SO_(3)^(2-),BO_(3)^(3-),NO_(2)^(-),C_(2)O_(4)^(2-),I^(-)`

Answer

To determine how many anions will give colorless acid vapors or gases when reacted with concentrated \( H_2SO_4 \), we will analyze each anion provided in the question:

1. **\( CH_3COO^- \) (Acetate Ion)**:
- Reaction: \( CH_3COO^- + H_2SO_4 \rightarrow CH_3COOH + SO_4^{2-} \)
- Product: Acetic acid (\( CH_3COOH \)) is colorless.
- Conclusion: Colorless gas/vapor.

2. **\( Cl^- \) (Chloride Ion)**:
- Reaction: \( Cl^- + H_2SO_4 \rightarrow HCl + SO_4^{2-} \)
- Product: Hydrochloric acid (HCl) is colorless.
- Conclusion: Colorless gas/vapor.

3. **\( Br^- \) (Bromide Ion)**:
- Reaction: \( Br^- + H_2SO_4 \rightarrow Br_2 + SO_4^{2-} \)
- Product: Bromine gas (\( Br_2 \)) is brown.
- Conclusion: Not colorless.

4. **\( S^{2-} \) (Sulfide Ion)**:
- Reaction: \( S^{2-} + H_2SO_4 \rightarrow H_2S + SO_4^{2-} \)
- Product: Hydrogen sulfide (\( H_2S \)) is colorless.
- Conclusion: Colorless gas/vapor.

5. **\( SO_3^{2-} \) (Sulfite Ion)**:
- Reaction: \( SO_3^{2-} + H_2SO_4 \rightarrow SO_2 + H_2O \)
- Product: Sulfur dioxide (\( SO_2 \)) is colorless.
- Conclusion: Colorless gas/vapor.

6. **\( BO_3^{3-} \) (Boron Trioxide Ion)**:
- Reaction: \( BO_3^{3-} + H_2SO_4 \rightarrow H_3BO_3 + SO_4^{2-} \)
- Product: Boric acid (\( H_3BO_3 \)) is colorless.
- Conclusion: Colorless gas/vapor.

7. **\( NO_2^- \) (Nitrite Ion)**:
- Reaction: \( NO_2^- + H_2SO_4 \rightarrow NO_2 + H_2O \)
- Product: Nitrogen dioxide (\( NO_2 \)) is brown.
- Conclusion: Not colorless.

8. **\( C_2O_4^{2-} \) (Oxalate Ion)**:
- Reaction: \( C_2O_4^{2-} + H_2SO_4 \rightarrow CO + CO_2 + H_2O \)
- Products: Carbon monoxide (\( CO \)) and carbon dioxide (\( CO_2 \)). Carbon dioxide is colorless.
- Conclusion: Colorless gas/vapor.

9. **\( I^- \) (Iodide Ion)**:
- Reaction: \( I^- + H_2SO_4 \rightarrow I_2 + SO_4^{2-} \)
- Product: Iodine gas (\( I_2 \)) is violet.
- Conclusion: Not colorless.

**Summary of Colorless Gas/Vapor Producing Anions**:
- \( CH_3COO^- \) (Acetate)
- \( Cl^- \) (Chloride)
- \( S^{2-} \) (Sulfide)
- \( SO_3^{2-} \) (Sulfite)
- \( BO_3^{3-} \) (Boron Trioxide)
- \( C_2O_4^{2-} \) (Oxalate)

**Total Count**: 6 anions produce colorless gases/vapors.

### Final Answer:
**6 anions will give colorless acid vapors/gases with concentrated \( H_2SO_4 \)**.