Benzene will not decolourise bromine water as it does not undergo addition reaction. It is highly saturated due to presence electron cloud above and below it.
Alkene + Bromine water in tetrachloromethane (CCl4): CnH2n + Br2 -> CnH2nBr2
Baeyer's test for unsaturation using KMnO4 . if the sol'n retains the purple color of the reagent , then it is an alkane. if the color disappears with formation of brown precipitate ,it indicates presence of unsaturated HC
Bromine in water or bromine water can be used to distinguish between an alkene and an alkyne. Alkenes will decolorize bromine water by undergoing addition reactions, while alkynes will not react under normal conditions and will not decolorize bromine water.
Bromine water is a dilute solution of bromine that is normally orange-brown in colour, but becomes colourless when shaken with an alkene. Alkenes can decolourise bromine water, while alkanes cannot.
No!! Benzene wont de colourise bromine water although it is an unsaturated compound ,as it is an aromatic compound and it does not undergo addition reaction.
The purple KMnO4 is decolourise
Alkene + Bromine water in tetrachloromethane (CCl4): CnH2n + Br2 -> CnH2nBr2
Baeyer's test for unsaturation using KMnO4 . if the sol'n retains the purple color of the reagent , then it is an alkane. if the color disappears with formation of brown precipitate ,it indicates presence of unsaturated HC
Bromine in water or bromine water can be used to distinguish between an alkene and an alkyne. Alkenes will decolorize bromine water by undergoing addition reactions, while alkynes will not react under normal conditions and will not decolorize bromine water.
Use bromine water (Br2) or acidified permanganate (H+/MnO4-) With permanganate: add the permanganate to the alkane and no reaction will occur, add the permanganate to the alkene and you will form a diol the solution will also turn from purple to colourless. With bromine water: add the bromine water to the alkane (plus you need sunlight) and you get a substitution reaction, this is a slow reaction. Add the bromine water to the alkene and you get an immediate addition reaction (this one does not need sunlight). When bromine water reacts with an alkene it is decolourised, the reddish brown bromine water turns from brown to colourless. This is because alkenes are unsaturated and contain a carbon to carbon double bond. If you did the bromine water test in a dark place say a cupboard then the alkene would decolourise but the alkane wouldn't because it needs UV/sunlight in order to react. in practice the cupboard is not necessary as the speed of decolourisation is so much faster with the alkene.
Bromine water is a dilute solution of bromine that is normally orange-brown in colour, but becomes colourless when shaken with an alkene. Alkenes can decolourise bromine water, while alkanes cannot.
Saturated hydrocarbon does not decolourise bromine water while unsaturated hydrocarbon decolourize it.
No!! Benzene wont de colourise bromine water although it is an unsaturated compound ,as it is an aromatic compound and it does not undergo addition reaction.
Alkenes, or hydrocarbons with at least one double bond undergo an addition reaction when combined with bromine (Br2). The general reaction is H2C=CH2 --> H2BrC--CBrH2, and it occurs readily. This reaction is a good way to identify alkenes because bromine has a reddish color, while alkanes and alkenes are colorless. So if bromine is added to an unknown hydrocarbon, the disappearance of the color is an indication of the presence of a pi bond.
bromine water
A positive test for an alkene is the addition of bromine water, which will turn from orange/red to colorless when it reacts with the alkene due to halogenation of the double bond. This test is used to confirm the presence of alkenes.
Bromine water reacts with alkenes through an electrophilic addition reaction where the pi bond of the alkene breaks, and bromine atoms are added to the carbon atoms. This reaction results in the decolorization of the bromine water, changing it from orange to colorless.