Tag: chemistry

solvent naphtha or benzin is used as a solvent for paints, resins, rubber etc.

Light oil or crude naphtha contains pyridine.
Whereas middle oil or carbolic oil contains phenol and naphthalene and green oil contains anthracene.

Anthracene oil shows green fluorescence. Hence, it is also named green oil.

All of the given statements are true regarding creosote oil.
It contains cresols along with some naphthalene and quinoline.
It is not worked up because its constituents are more easily obtained by synthetic methods.
It is used as such under the name of creosote oil for the preservation of wood and for the manufacture of some disinfectants.

Green oil contains anthracene that is used for the manufacture of alizarin dyes.

 Pitch or undistilled residue is used in varnishes, road-making and protecting wood and metal work

The percent of carbon present in pitch is 92-94%.

Coal tar is a complex mixture of phenols, polycyclic aromatic hydrocarbons (PAHs), and heterocyclic compounds but it is mainly used as the main source for aromatic compounds.

When fractional distillation of coal tar is carried out,  the maximum percentage is of pitch. Pitch is undistilled residue. It is about 50-60%.

During the fractional distillation of coal tar, the fraction which has minimum percentage is light oil or crude naphtha. It is obtained only $1.5-2\%$ in the distillation.