Khimiia 10 Klass Rudzitis 2 Prakticheskaia Rabota 【Tested & Working】

The blue precipitate dissolves, forming a bright blue (cornflower blue) transparent solution.

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 khimiia 10 klass rudzitis 2 prakticheskaia rabota

2CH3COOH+Na2CO3→2CH3COONa+H2O+CO2↑2 cap C cap H sub 3 cap C cap O cap O cap H plus cap N a sub 2 cap C cap O sub 3 right arrow 2 cap C cap H sub 3 cap C cap O cap O cap N a plus cap H sub 2 cap O plus cap C cap O sub 2 up arrow Step B: Identifying Polyhydric Alcohols (e.g., Glycerol) The blue precipitate dissolves, forming a bright blue

Below is a structured report (essay-style) for this practical work. 1. Define the Objective Summary Table of Results Na2CO3cap N a sub

The blue mixture changes to yellow and then forms a brick-red precipitate ( Cu2Ocap C u sub 2 cap O Equation (for acetaldehyde):

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

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.