Question

How will you distinguish C₂H₅Br from C₆H₄Br?

How will you distinguish between the following pair of compounds?

Ethyl bromide and bromobenzene

Answer 1

	C2H5Br (Ethyl Bromide)	C6H4Br (Bromobenzene)
Type of compound	Alkyl halide	Aryl halide (aromatic compound)
Physical state	It is a colorless liquid.	It is a colorless to pale yellow liquid.
Boiling point	It has a relatively lower boiling point due to its alkyl nature.	It has a higher boiling point because of the aromatic ring.
Solubility in water	Slightly soluble in water.	Insoluble in water due to non-polar aromatic structure.
Nature of C-Br bond	The bromine is attached to sp3 hybridized carbon (alkyl).	The bromine is attached to sp2 hybridized carbon (aryl).
Reaction with aqueous NaOH	Reacts readily by nucleophilic substitution to form ethanol.	Does not react readily with NaOH due to resonance stabilization.
Wurtz reaction	Reacts with sodium metal to form butane (alkane).	Reacts with sodium metal to give biphenyl (aromatic).
Reactivity in SN2	Undergoes SN2 reactions easily.	Does not undergo SN2 reactions due to strong C–Br bond and aromatic ring.
Volatility	More volatile due to weaker intermolecular forces.	Less volatile due to stronger intermolecular forces and aromaticity.