Polarity testing. Aim: To determine whether the following liquids are polar or non-polar in nature

                                                                           Observations

Inference

Wherever deflection occurs, the molecule is polar. This is because a deflection on stream of liquid from the burette by a charged polythene rod indicates that the liquid consists of polar molecules. A polar molecule has a slight positive or negative charge and so when it is brought near to a charged rod it undergoes deflection.

Errors and Improvements

• We should take care not to touch the liquid with the polythene rod to make sure that deflection is not affected.
• Any two compounds should not be kept close to one another as the vapours from one compound may affect the polarity of the other.
• We should keep rubbing the polythene rod either to your hair or on a woollen cloth to make sure that it is charged.
• We should clean the apparatus properly to remove any other impurities.