What does Br2 in CH2Cl2 do?

One such reaction is with bromine (Br2) in dichloromethane (CH2Cl2). When it is dripped slowly into a sample of alkene, the bromine reacts with the alkene to form a nearly colorless organic 1,2-dibromide. Because the Br2 is consumed, the mixture loses the reddish-orange color.

What happens when butene reacts with bromine?

Unsaturated hydrocarbons such as alkenes and alkynes are much more reactive than the parent alkanes. The reaction between 2-butene and bromine to form 2,3-dibromobutane is just one example of the addition reactions of alkenes and alkynes.

What happens when Br2 reacts with an alkene?

Alkenes react in the cold with pure liquid bromine, or with a solution of bromine in an organic solvent like tetrachloromethane. The double bond breaks, and a bromine atom becomes attached to each carbon. The bromine loses its original red-brown color to give a colorless liquid.

What happens when but 2 ene reacts with Br2?

As but-2-ene bubbles through the bromine solution and reacts with the bromine, the bromine adds across the double bond and so the solution changes from brown to colourless. This is why the decolouration of a bromine solution is used as an analytical test for alkenes.

What does CH2Cl2 do in a reaction?

Inert solvents such as methylene chloride (CH2Cl2) or carbon tetrachloride (CCl4) are typically used for halogen additions be- cause these solvents dissolve both halogens and alkenes.

How does alkane react with bromine?

Alkanes and alkenes tend to be colourless. So, when bromine water is added to an alkane or alkene and mixed well, initially the mixture turns a red-brown colour due to the bromine. As the bromination reaction proceeds, the reaction mixture de-colourises (loses its red-brown colour).

When CIS but 2 ene is treated with Br2 in ccl4 medium the product formed will be?

-The product formed is an enantiomeric pair as they are non-superimposable mirror images of each other. The pair is (2R, 3R) and (2S, 3S) dibromobutane. Hence the correct answer is: d) mixture of (2R, 3R) and (2S, 3S) dibromobutane.

When but 2 ene is shaken with bromine water the brown bromine water is Decolourised What is the product of this reaction?

Alkenes decolourise bromine water. This is complicated by the fact that the major product isn’t 1,2-dibromoethane. The water also gets involved in the reaction, and most of the product is 2-bromoethanol.