Question

kerosene does not decolorize bromine water where as cooking oil do

Answer 1

According to the data mentioned in the question that,

Kerosene does not decolorize bromine water where as cooking oil do.

The chemical reason behind this phenomenon is,there are unsaturated hydrocarbons present in the cooking oil, that's why it decolorize the normal bromine water.

And,on the other hand,there are no unsaturated hydrocarbons in the Kerosine, that's why it doesn't decolorize the bromine water