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

Carboxylic acids can be identified by their acidity or their reaction with carbonates. Add a drop of litmus or a small amount of Na2CO3cap N a sub 2 cap C cap O sub 3 to the sample. Observation: Litmus turns red; Na2CO3cap N a sub 2 cap C cap O sub 3 produces effervescence (bubbles of CO2cap C cap O sub 2 Equation:

Polyhydric alcohols react with copper(II) hydroxide at room temperature. Add freshly prepared to the test tube.

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.

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

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

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)