Distinction between pairs of compounds
3-Bromoprop-1-ene `(CH_(2)=CH-CH_(2)Br)` and 1-Bromopropane `(CH_(3)CH_(2)CH_(2)Br)`.
(a) `Br_(2)` test.
(b) Baeyer's reagent test.

Explanation

3-Bromoprop-1-ene contains a C = C double bond. So, it decolorises orange colour of `Br_(2)+C Cl_(4)` solution. 1-Bromopropane does not contain C=C, so it does not give this test.
`overset(1)CH_(2)=undersetunderset(("Allyl bromide"))("3-Bromoprop-1-ene")(overset(2)CHoverset3CH_(2)Br)+Br_(2)overset(C Cl_(4))rarrunderset("1,2,3-Tribromopropane (Colourless)")(oversetoverset(CH_(2)-)("| ")("Br")oversetoverset(CHCH_(2)Br)("| ")("Br "))`
(b) 3-Bromoprop-1-ene decolories the pink colour of Baeyer.s reagent (a dilute solution of alkaline `KMnO_(4)`) since it conains C = C. 1-Bromopropane does not contain C = C, so it does not give this test.
`underset("3-Bromoprop-1-ene")(CH_(2)=CHCH_(2)Br)+undersetunderset(("Pink"))("From alk "KMnO_(4))(H_(2)O+O)rarrundersetunderset("Colourless")("3-Bromopropane-1, 2-diol")(CH_(2)OH-CHOH-CH_(2)Br)`