DETERMINATION OF SURFACE TENSTION OF GIVEN SAMPLE BY DROP WEIGHT METHOD

Aim: To determine the surface tension of given sample by drop weight method using stalagmometer.
Requirements: Apparatus: Stalagmometer, Beakers, Measuring Cylinder. .
Chemicals: Water, Acetone, Ethanol, Benzene. .
Principle: The stalagmometer consists of a glass capillary tube with a bulb at the middle. There is a capillary bore at the tip of the stalagmometer. The surface tenstion of the liquid can be calculated using following formula. .
v1= w1/w2.v2.
Where .
v1= Surface tension of given sample.
v2= Surface tension of water.
w1= Weight of given sample.
w2= Weight of water.
Procedure: The liquid which is to be tested was sucked into the clean stalagmometer upto mark A. Then it was allowed to fall down due to gravity. 30 drops of liquid were collected in a beaker. The weights of the drops were determined by using electronic balance. The procedure was repeated three times to obtain mean value. Then the surface tension calculated using above formula. .
Tabulation: .

Report: From the above experiment. We concluded that the surface tension of given sample was found to be___________.