Khimiia 10 Klass Rudzitis 2 Prakticheskaia Rabota -

In the 10th-grade chemistry curriculum by Rudzitis and Feldman, Practical Work No. 2 typically focuses on the This work is designed to apply qualitative analysis to distinguish between various classes of organic substances.

Polyhydric alcohols react with copper(II) hydroxide at room temperature. Add freshly prepared to the test tube. khimiia 10 klass rudzitis 2 prakticheskaia rabota

The blue precipitate dissolves, forming a bright blue (cornflower blue) transparent solution. In the 10th-grade chemistry curriculum by Rudzitis and

Both aldehydes and glucose (which contains an aldehyde group) react with upon heating. Add and heat the mixture gently. Add freshly prepared to the test tube

CH3CHO+2Cu(OH)2ΔCH3COOH+Cu2O↓+2H2Ocap C cap H sub 3 cap C cap H cap O plus 2 cap C u open paren cap O cap H close paren sub 2 cap C cap H sub 3 cap C cap O cap O cap H plus cap C u sub 2 cap O down arrow positive 2 cap H sub 2 cap O 4. Summary Table of Results Na2CO3cap N a sub 2 cap C cap O sub 3 Gas evolution ( CO2cap C cap O sub 2 Glycerol Bright blue solution Aldehyde / Glucose Brick-red precipitate 5. Final Conclusion

This indicates the presence of multiple hydroxyl ( −OHnegative cap O cap H ) groups on adjacent carbon atoms. Step C: Identifying Aldehydes or Glucose

To perform the identification, the following reagents are required: Freshly prepared (copper(II) hydroxide), formed by mixing NaOHcap N a cap O cap H CuSO4cap C u cap S cap O sub 4 Blue litmus paper or universal indicator. Na2CO3cap N a sub 2 cap C cap O sub 3 (sodium carbonate) or NaHCO3cap N a cap H cap C cap O sub 3 (sodium bicarbonate). Test tubes, a spirit lamp, and a test tube holder. 3. Execution of Qualitative Tests Step A: Identifying Carboxylic Acids (e.g., Acetic Acid)