Presentation on theme: "Laboratory Work №1 Qualitative detection of carbon, hydrogen, chlorine in organic compounds."— Presentation transcript:
Laboratory Work №1 Qualitative detection of carbon, hydrogen, chlorine in organic compounds
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.
Laboratory equipment Laboratory iron stand Icon ring beaker Volumetric flask Alcohol burner test tube Evaporating dish
Experiment №1. Qualitative detection of carbon in organic compounds CO 2 Ca(OH) 2 Ca(OH) 2 + CO 2 ->-> CaCO 3 + H 2 O CaCO 3 CuSO 4 CuO, paraffine Cu 5H 2 O
Experiment №2. Qualitative detection of hydrogen in organic compounds H2OH2O CuSO H 2 O -> CuSO 4 * 5 H 2 O 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. CuO Paraffin Cu C 23 H CuO -> 70Cu + 23CO H 2 O
Experiment: Qualitative detection of carbon and hydrogen in organic compounds CO 2 Ca(OH) 2 Ca(OH) 2 + CO 2 ->-> CaCO 3 + H 2 O CaCO 3 CuSO 4 CuO, paraffin Cu 5H 2 O C 23 H CuO -> 70Cu + 23CO H 2 O CuSO H 2 O -> CuSO 4 * 5 H 2 O
Your observations Copper (II) oxide reduced to copper, so we observe change in color from black to red. C 23 H CuO -> 23 CO H 2 O + 70 Cu Colorless copper (II) sulfate changed its color to blue because of formation of copper (II) sulfate pentahydrate. CuSO 4 + 5H 2 O -> CuSO 4 * 5H 2 O Carbon dioxide formed as a result of reaction gives precipitate of the carbonate by passing into limewater solution. Ca(OH) 2 + CO 2 -> CaCO 3 + H 2 O
H2OH2O 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. Sugar carbonizes i.e. carbon as pure element coke is produced t C 12 H 22 O 11 -> 12 C + 11 H 2 O
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
Insert the copper wire into the organic solid substance to be analyzed
Heat the copper wire again. Copper forms copper (II) chloride and the flame will take the characteristic green blue color.
Test № 1 Put correct words instead of dots. 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 …………… H malaxite CO 2 Cl oxygen O reducing agent Blue vitrol SO 2 oxidizing agent C CO copper
Test № 2 Put correct word instead of dots 1. The color of copper (II) sulfate changes as a result of ……….. 2. Molecular formula of paraffin ……. 3. Formation of CuSO 4 * 5H 2 O proves existence of … 4. The formula of tetrachloromethane ……. 5. The flame assumes the green – blue color because of the presence …. CH 4 C 8 H 18 SCCl 4 dehydration HCHCl 3 hydrogenationC 23 H 48 C 23 H 46 hydration OCu Cl C