See also:

• XYLENE, or DIMETHYL BENZENE, C6H4(CH3)2

XYLENE, or DIMETHYL See also:

• BENZENE, C6H6

BENZENE, See also:

• C6H4
• C6H4(CH213r)2

C6H4(See also:

• CH3

CH3)2  . Three isomeric See also:

• HYDROCARBONS

hydrocarbons of this See also:

• FORMULA
• FORMULA (Lat. diminutive of forma, shape, pattern, &c., especially used of rules of judicial procedure)

formula exist; they occur in the See also:

• LIGHT

light oil fraction of the See also:

• COAL

coal See also:

• TAR

tar distillate, but they cannot be separated by fractional See also:

• DISTILLATION (from the Lat. distillare, more correctly destillare, to drop or trickle down)

distillation owing to the closeness of their boiling points . The mixture can be separated by shaking with sulphuric See also:

• ACID (from the Lat. root ac-, sharp; acere, to be sour)

acid, whereupon the ortho and See also:

• META

meta forms are converted into soluble sulphonic acids, the See also:

• PARA
• PARA (officially BELEM; sometimes BELEM DO PARA)

para See also:

• FORM (Lat. forma)

form being soluble only in concentrated acid; the ortho and meta acids may be separated by See also:

• CRYSTALLIZATION

crystallization of their salts or sulphonamides . Ortho-See also:

• XYLENE, or DIMETHYL BENZENE, C6H4(CH3)2

xylene is obtained from ortho-bromtoluene, methyl iodide and See also:

• SODIUM [symbol Na, from Lat. natrium; atomic weight 23.00 (0=16)]

sodium as a colourless See also:

• MOBILE

mobile liquid boiling at 142°, melting at -28°, and having a specific gravity of x.8932 at o° . Oxidation by See also:

• POTASSIUM [symbol K (from kalium), atomic weight 39.114 0=16)]

potassium permanganate gives See also:

• PHTHALIC

phthalic acid; whilst chromic acid gives See also:

• CARBON (symbol C, atomic weight 12)

carbon dioxide and See also:

• WATER

water . Meta- or iso-xylene, the most important isomer, may be prepared by See also:

• NUCLEUS (Lat. for the kernal of a nut, nux, the stone of fruit)

nucleus-synthetic reactions, or by distilling mesitylenic acid, C6H3(See also:

• CH3

CH3)2CO2H, an oxidation product of mesitylene, C6H3(CH3)3, which is produced on the condensation of See also:

• ACETONE, or DIMETHYL KETONE

acetone, with See also:

• LIME
• LIME (O. Eng. lim, Lat. limes, mud, from linere, to smear)

lime; this reaction is very important, for it orientates meta-compounds . It boils at 139°, melts at -54°, and has a specific gravity of o•8812 . Para-xylene is obtained when camphor is distilled with See also:

• ZINC

zinc chloride, but it is best prepared from para-brom-See also:

• TOLUENE, or METHYLBENZENE

toluene or dibrombenzene, methyl iodide and sodium . Dilute nitric acid oxidizes it first to para-toluic acid and then to See also:

• TEREPHTHALIC

terephthalic acid . It boils at 138°, melts at 15°, and has a specific gravity of o•88o1 at o° .