Is p-xylene the same as xylene?
No, p-xylene isn't the same as xylene.
p-Xylene (para-xylene) is an aromatic hydrocarbon. It is one of the three isomers of dimethylbenzene known collectively as xylenes.
Key Differences
Formula: All xylenes have the same chemical formula: C8H10
Structure: All are dimethylbenzenes. The "p-" (short for para) means its two methyl groups attach to opposite positions (1 and 4) of the benzene ring. This is different from ortho-xylene (methyl groups next to each other) and meta-xylene (one carbon apart between the two methyl groups).
Properties: These structural differences cause small variations in physical traits. For example, p-xylene has a relatively high melting point (13.26 °C) and is often a crystalline solid at room temperature. By contrast, ortho- and meta-xylenes remain liquids under the same conditions.
Usage: Mixed xylenes work well as solvents. But p-xylene stands out—it is the key raw material for making terephthalic acid (PTA), which is further used to produce PET plastics and polyester fibers.