Why does bromine work well when testing wheather a hydrocarbon is saturated or unsaturated?
The bromine test is used to determine if the colorless organic compound contains any double C=C bonds (the alkene functional group). Bromine does not react with an alkane because the alkane contains only single C-C bonds which cannot add the bromine. Alkanes merely dilute the red-brown bromine color to an orange or yellow color in the absence of a strong catalyst. Due to their C=C double bonds which can be broken, alkenes react readily with bromine to produce saturated dibromoalkanes. When an alkene is reacted with bromine, the red-brown color of the bromine is immediately lost due to the reaction of the bromine. Alkane + bromine (No strong light or heat) results in diluted solution colored orange or yellow indicating no reaction. Alkane + bromine (heat or strong light acting as a catalyst) results in the brown red color of bromine slowly disappearing. Alkene + bromine results in the red brown color of bromine rapidly or immediately disappearing giving a colorless solution Aromatic hyd
