Question

Give five differences between aliphatic and aromatic compounds.

Answer 1

In general, an aliphatic compound (sometimes referred to as an alkane) is primarily characterized by the fact that all of the carbon-carbon bonds that make up the skeleton of the molecule are single bonds. That means no double or triple carbon-carbon bonds of any kind are allowed.
Aromatic compounds are similar to aliphatic compounds in the sense that they're both made of carbon, however they are also very different from one another in other ways. An aromaticorganic compound is characterized by the fact that they contain both a ring structure and a network of alternating double-single-double-single bonds all around the ring. 
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Answer 2

These are: 1: If the compound burns with a sooty flame then it may be aromatic, otherwise aliphatic. 2:Heat the compound with HNO3 and H2SO4. After cooling it put this mixture in water, If yellow color appears, then the compound may be aromatic due to nitration of the ring.