Prakticheskaia Rabota - Khimiia 10 Klass Rudzitis 2

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

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)

Below is a structured report (essay-style) for this practical work. 1. Define the Objective khimiia 10 klass rudzitis 2 prakticheskaia rabota

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

The blue precipitate dissolves, forming a bright blue (cornflower blue) transparent solution. CH3CHO+2Cu(OH)2ΔCH3COOH+Cu2O↓+2H2Ocap C cap H sub 3 cap C

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.

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: Na2CO3cap N a sub 2 cap C cap

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