The primary goal of this experiment is to use qualitative chemical reactions to identify unknown organic substances in test tubes, such as . 2. Prepare Reagents and Equipment
The blue mixture changes to yellow and then forms a brick-red precipitate ( Cu2Ocap C u sub 2 cap O Equation (for acetaldehyde): khimiia 10 klass rudzitis 2 prakticheskaia rabota
The blue precipitate dissolves, forming a bright blue (cornflower blue) transparent solution. The primary goal of this experiment is to
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) To perform the identification, the following reagents are
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