The Chemical and Physical Properties
eugene-a-xylol Xylol, the traditional name for xylene, is an aromatic hydrocarbon with the formula C8H10. Its behavior as a solvent, its flammability, and the way it moves through air all trace back to a handful of physical properties. This is a reference rundown of those numbers and what they mean in practice.
Structure and isomers
Chemically, xylol is dimethylbenzene: a benzene ring carrying two methyl groups. Those two groups can sit in three different pairs of positions, which gives three isomers, ortho-, meta-, and para-xylene. Commercial xylol is usually a blend of all three, sold as “mixed xylenes,” often with a little ethylbenzene along for the ride. The isomers differ slightly in melting and boiling points but behave much alike as solvents.
Physical properties at a glance
| Property | Typical value (mixed xylenes) |
|---|---|
| Chemical formula | C8H10 |
| Molar mass | About 106.2 g/mol |
| Appearance | Clear, colorless liquid |
| Odor | Sweet, aromatic |
| Boiling point | 137-144 °C (279-291 °F) |
| Melting point | Varies by isomer, roughly -47 to 13 °C |
| Density | About 0.86-0.88 g/cm³ (lighter than water) |
| Flash point | About 27-32 °C (81-90 °F) |
| Autoignition temperature | About 460-530 °C |
| Vapor density | About 3.7 (heavier than air) |
| Solubility in water | Practically insoluble |
| Miscibility | Mixes with most organic solvents |
What the numbers mean
A few of these matter more than the rest in day-to-day handling:
- Lighter than water and insoluble: spilled xylol floats and spreads rather than mixing in, which shapes both cleanup and firefighting.
- Vapor heavier than air: fumes sink and can pool in pits, basements, and low, still corners.
- Low flash point: at normal room temperature xylol can give off enough vapor to ignite, so it is handled as a flammable liquid.
- Moderate boiling point: it evaporates slower than acetone but faster than heavy oils, the balance that makes it a useful coatings solvent.
Quick answers
Is xylol heavier or lighter than water? Lighter. It floats on the surface.
Does xylol conduct electricity? No. Like most hydrocarbons it is a poor conductor, which is why static can build up during transfer and needs to be controlled with grounding.