ANION Analysis STEPWISE in 15 minutes class 11 and 12 Chemistry Practical.

Introduction

This tutorial provides a comprehensive guide to conducting anion analysis in chemistry, specifically tailored for Class 11 and 12 students. You will learn how to systematically identify various anions in salt samples using established chemical tests, all within a 15-minute timeframe. This practical knowledge is essential for your chemistry practical exams and reinforces fundamental concepts in qualitative analysis.

Step 1: Preparation for Anion Analysis

• Gather all necessary materials:
  • Salt sample
  • Test tubes and rack
  • Reagents for each anion test (e.g., dilute acids, silver nitrate, barium chloride)
  • Safety gear (gloves, goggles, lab coat)
• Ensure that you have access to the flow chart for quick reference during the tests. You can find it here.

Step 2: Conducting the Carbonate Test

• Add a few drops of dilute hydrochloric acid (HCl) to the salt sample.
• Observe for effervescence (bubbles) indicating the presence of carbon dioxide, which confirms the presence of carbonate ions (CO3²⁻).
• Practical Tip: If you see bubbles, you can further confirm by passing the gas through lime water; it will turn milky.

Step 3: Conducting the Sulphite Ion Test

• Mix the salt with dilute hydrochloric acid and add a few drops of barium chloride (BaCl2).
• A white precipitate indicates the presence of sulphite ions (SO3²⁻).
• Common Pitfall: Ensure the solution is clear before adding BaCl2 to avoid confusion with other precipitates.

Step 4: Conducting the Nitrite Ion Test

• Add a few drops of dilute acetic acid and a few drops of sulfanilic acid to the salt solution.
• Follow with a few drops of naphthylamine and observe for a red color, indicating nitrite ions (NO2⁻).
• Practical Tip: Conduct this test in a well-ventilated area due to the odor of nitrites.

Step 5: Conducting the Sulphide Ion Test

• Mix the salt with dilute hydrochloric acid and check for the formation of black precipitate (lead sulfide).
• This indicates the presence of sulphide ions (S²⁻).
• Common Pitfall: Ensure that the acid is added slowly to avoid excessive reaction.

Step 6: Conducting the Chloride Ion Test

• Add a few drops of silver nitrate solution to the salt solution.
• A white precipitate of silver chloride (AgCl) indicates the presence of chloride ions (Cl⁻).
• Practical Tip: Conduct the test in a dark environment to prevent light-sensitive reactions.

Step 7: Conducting the Bromide Ion Test

• Similar to the chloride test, add silver nitrate to the salt solution.
• A pale yellow precipitate indicates bromide ions (Br⁻).
• Common Pitfall: Ensure the solution is not too concentrated, as this can affect the color of the precipitate.

Step 8: Conducting the Iodide Ion Test

• Again, add silver nitrate to the salt solution.
• A bright yellow precipitate indicates the presence of iodide ions (I⁻).
• Practical Tip: Use fresh reagents for more accurate results.

Step 9: Conducting the Nitrate Ion Test

• For the Brown Ring Test, add a few drops of concentrated sulfuric acid to the sample, then add iron(II) sulfate slowly.
• A brown ring at the interface indicates nitrate ions (NO3⁻).
• Common Pitfall: Be careful when adding sulfuric acid; do it slowly to avoid spillage.

Step 10: Conducting the Sulphate Ion Test

• Add a few drops of barium chloride to the salt solution.
• A white precipitate indicates the presence of sulphate ions (SO4²⁻).
• Practical Tip: Ensure the sample is filtered to remove impurities before testing.

Step 11: Conducting the Phosphate Ion Test

• Add a few drops of ammonium molybdate to the solution and heat gently.
• A yellow precipitate indicates the presence of phosphate ions (PO4³⁻).
• Common Pitfall: Avoid excessive heating as it may alter the results.

Step 12: Conducting the Oxalate Ion Test

• Add calcium chloride to the salt solution.
• A white precipitate of calcium oxalate indicates the presence of oxalate ions (C2O4²⁻).
• Practical Tip: Make sure to use fresh calcium chloride for accurate results.

Step 13: Conducting the Acetate Ion Test

• Add a few drops of concentrated sulfuric acid to the salt solution.
• A characteristic smell of vinegar indicates the presence of acetate ions (CH3COO⁻).
• Common Pitfall: Conduct this test in a fume hood or well-ventilated area due to the strong odor.

Conclusion

By following these step-by-step instructions, you can effectively conduct anion analysis for various ions commonly found in salts. Familiarize yourself with each test and practice them to gain confidence. For additional resources and detailed videos, refer to the links provided in the description. Mastering these techniques will not only help you in practical examinations but also deepen your understanding of qualitative analysis in chemistry.