Practical : 1
To determine the boiling point of given liquid organic compound.
Aim : To determine the boiling point of given liquid organic compound.
Apparatus : Thiele's tube. fusion tube, capillary tube, thermometer, thread.
Chemical : Given organic liquid compound, paraffin liquid.
Theory :
1) The boiling point of liquid substance is defined as the temperature at which vapour pressure of liquid is equal to atmospheric pressure.
2) The boiling point of liquid substance is to be taken to check the purity of liquids.
Generally pure liquids boils at fixed temp.
Procedure :
1) The Thiele's tube containing paraffin liquid of fix to the stand as shown in diagram.
2) Fix fusion tube to thermometer using thread. Take few drops of given liquid compound into fusion tube whose boiling point is to be determined. The closed end of fusion tube and mercury bulb of thermometer should lie in same line.
3) Take capillary tube closed at one end and keep into fusion tube in inverted fusion.
4) Immerse thermometer along with fusion tube and capillary tube into Thiele's tube containing Paraffin liquid. Here the open end of fusion tube should not dip into paraffin liquid.
5) Heat Thiele's tube gently.
Record the temperature, when the rate of bubbling is maximum. This temperature is called boiling point of that liquid.
6) In higher boiling point compounds during heating first of all liquid compound inserts or enters into capillary tube and then starts maximum bubbles. This temperature is the boiling point of that liquid compound.
Result :
1) The boiling point of compound
I) is 76°C
2) The boiling point of compound
II) is 120°C
3) The boiling point of compound
III) is 180°C
They compound is first is Ethyl alcohol [ ethanol]
They compound seconds is acetyl acid [ ethanoic acid]
They compound third is Aniline [ benzamine ]
Practical : 2
To prepare phthalic anhydride from phthalic acid by sublimation reaction
Aim : To prepare phthalic anhydride from phthalic acid by sublimation reaction.
Apparatus : China dish, Glass funnel, filter paper, Wire gauze, Cotton Plug, glass rod etc.
Chemicals : Phthalic acid
Reaction :
Theory:
1) The phthalic acid heat on sublimation gives phthalic anhydride.
Defi :
The conversation of solid substance into gases state without formation of liquid state.
The substance which under goes is called sublime (phthalic acid). while the product is called sublimate (phthalic anhydride).
The advantage of sublimation reaction that the product having highest degree of purity.
This reaction suffers by the drawback the yielded is very poor (less).
Procedure :
1) Take clean China dish containing 2-3gm phthalic acid.
2) take an ordinary filter paper and make several holes at its center.
3) Keep this fitter paper on China dish containing phthalic acid.
4) Take a Glass funnel fix cotton plug in its nojal part.
5) Place this funnel on fetter inverted fashion.
6) Allow the heat China dish gently. The phthalic acid sublimation the wapar on phthalic acid.
7) Allow the cool china dish, the fine Luminous thin filament like crystals of phthalic anhydride get deposited on inner walls on funnel as well as on filter paper.
8) Collect this crystals on filter paper using glass rod. Report the melting point & yield phthalic anhydride.
Results:
The yield of phthalic anhydride 0.044gm.
The melting point phthalic anhydride 127°C.