1. Qualitative detection of
Laboratory Work №1
Qualitative detection of
carbon,
hydrogen,
chlorine
in organic compounds

2. PROCEDURE
1. Put copper (II) oxide and paraffin into the test tube, then heat it carefully until paraffin melts and shake the test tube.
2. Place the test tube into the laboratory iron stand and add some copper (II) sulfate
3. Close the test tube by a bent delivery test tube the other end of which is dipping into lime water contained in flame.

3. Laboratory equipment Icon ring test tube beaker Volumetric flask
Laboratory iron stand
Evaporating dish
Alcohol burner

4. Experiment №1. Qualitative detection of carbon in organic compounds
CuO, paraffine
CO2 Cu
CuSO4
5H2O
Ca(OH)2 + CO2 ->
-> CaCO3 + H2O
CaCO3
Ca(OH)2

5. Experiment №2. Qualitative detection of hydrogen in organic compounds
CuSO4
+ 5 H2O -> CuSO4 * 5 H2O Cu
CuO
H2O
Paraffin
C23H CuO -> 70Cu + 23CO2 + 24H2O
When mixture of paraffin and copper (II) oxide is heated alkanes are oxidized to carbon dioxide and water. Water forms hydrate with copper (II) sulfate which has blue color. Copper (II) oxide is reduced to red copper.
So in paraffin hydrogen exists.

6. Experiment: Qualitative detection of carbon and hydrogen in organic compounds
CuSO H2O -> CuSO4 * 5 H2O
CuO, paraffin Cu
CO2
CuSO4
5H2O
Ca(OH)2 + CO2 ->
-> CaCO3 + H2O
CaCO3
Ca(OH)2
C23H CuO -> 70Cu + 23CO2 + 24H2O

7. Your observations
Copper (II) oxide reduced to copper, so we observe change in color from black to red.
C23H CuO -> 23 CO2 + 24H2O + 70 Cu
Colorless copper (II) sulfate changed its color to blue because of formation of copper (II) sulfate pentahydrate.
CuSO4 + 5H2O -> CuSO4 * 5H2O
Carbon dioxide formed as a result of reaction gives precipitate of the carbonate by passing into limewater solution.
Ca(OH)2 + CO2 -> CaCO3 + H2O

8. Experiment № 3. Detection of carbon
in sugar (sucrose) by carbonization test
Put some amount of sugar into an evaporation dish . Then heat it.
Sugar carbonized.
H2O
Sugar carbonizes i.e. carbon as pure element coke is produced t
C12H22O > 12 C H2O

9. Experiment №4. Qualitative detection of chlorine in organic compounds – Beilstein test
Heat a copper wire in a bunsen flame until the color is non-luminous

10. Insert the copper wire into the organic solid substance to be analyzed

11. Heat the copper wire again.
Copper forms copper (II) chloride and the flame will take the characteristic green blue color.

12. Test № 1 Put correct words instead of dots.
SO2 C H O
CO2
oxygen
reducing agent
Blue vitrol CO Cl
copper
malaxite
oxidizing agent
1. Lime water forms precipitate when …….. passes through the solution
2. Formation of precipitate proves the existence of ……
3. In the reaction copper (II) oxide - …………
4. …. is formed from copper (II) oxide
5. Unaqueous copper (II) sulfate becomes blue because ……………

13. Test № 2 Put correct word instead of dots
hydration
C8H18
dehydration
hydrogenation
C23H48
C23H46 H O S Cl C
CCl4
CHCl3
CH4 Cu
1. The color of copper (II) sulfate changes as a result of ………..
2. Molecular formula of paraffin …….
3. Formation of CuSO4* 5H2O proves existence of …
4. The formula of tetrachloromethane …….
5. The flame assumes the green – blue color because of the presence ….