Testing the Presence of C=C Double Bond

Okay, your teacher gave you two solutions. Solution A is pentane and solution B is pentene. How would you distinguish between the two? Prepare two test tubes. Add a few drops of bromine water to both of the tubes containing pentane and pentene, respectively. Observe! That solution that decolourizes is PENTENE. Alkene undergoes halogenation with bromine to produce dibromopentane. No reaction between pentane and bromine water, reddish-brown colour remains.