Reagents for Nitrogen Oxides Analysis
The analysis of oxides of nitrogen (NOx) typically involves methods that first convert NOx into nitrite ions ($NO_2^-$) or involve reactions sensitive to nitrogen oxides. A common approach uses colorimetric detection.
Key Reagents and Their Roles
The question asks for the set of reagents used in the analysis. Let's examine the components of the correct option:
- Sulphanilic acid: This aromatic amine is a primary reagent in the Griess reaction. It diazotizes in the presence of nitrite ions ($NO_2^-$).
- NEDA (N-(1-Naphthyl)ethylenediamine dihydrochloride): This coupling agent reacts with the diazotized sulphanilic acid to form a highly colored azo dye. The intensity of the color is proportional to the concentration of nitrite (and thus NOx).
- H2O2 (Hydrogen Peroxide): Often used in specific procedures for NOx analysis, potentially aiding in the conversion or reaction steps.
- HNO3 (Nitric Acid): Can be used as a standard or involved in the sample preparation or reaction mechanism depending on the specific analytical protocol for NOx.
Evaluating Other Options
Other options are less suitable:
- Option 2 uses Sulphamic acid, which can sometimes substitute for sulphanilic acid, but sulphanilic acid is the classic Griess reagent.
- Option 3 includes Nicotine and H2O, which are not standard reagents for this analysis.
- Option 4 includes Sulphomolybdic acid and H2SO4, which are not the primary reagents for the standard colorimetric NOx analysis using the Griess method.
Conclusion
The set comprising Sulphanilic acid, NEDA, H2O2, and HNO3 represents a combination of reagents commonly employed in specific analytical methods for the determination of oxides of nitrogen.
Important Questions from Environmental pollution
Photochemical smog is a resultant of the reaction among
Which of the following is NOT responsible for the degradation of our environment?
Why is there a concern about copper smelting plants?
1. They may release lethal quantities of carbon monoxide into environment.
2. The copper slag can cause the leaching of some heavy metals into the environment.
3. They may release sulphur dioxide as a pollutant.
Select the correct answer using the code given below.
Magnetite particles, suspected to cause neurodegenerative problems are generated as environmental pollutants from which of the following?
1. Brakes of motor vehicles
2. Engines of motor vehicles
3. Microwave ‘Stoves within homes
4. Power plants
5. Telephone lines
Select the correct answer using the code given below.
Considering the primary atmospheric roles and radiative forcing characteristics, which of the following gases is not typically categorized as a long-lived, well-mixed greenhouse gas contributing directly to the Earth's warming, but rather is known for its role in atmospheric aerosol formation and acid deposition?
