100 NON-METALS AND THEIR COMBINATIONS. 



14. SULPHUR. 



Sii = 32 (31.97). 



Occurrence in nature. Sulphur is found in the uncombined 

 state in volcanic districts, the chief supply being derived from 

 Sicily. In combination sulphur is widely diffrsed in the form of 

 sulphates (gypsum, CaSO 4 .2H 2 O), and frequently as sulphides (iron 

 pyrites, FeS 2 , galena, PbS, cinnabar, HgS, etc.). Sulphur enters also 

 into organic compounds, during the decomposition of which sulphur 

 is evolved as hydrogen sulphide, which gas is also a constituent of 

 some waters. 



Properties. Sulphur is a yellow, brittle, solid substance, having 

 neither tastejaor_ odor. It is insoluble in water and nearly so in 

 alcohol; soluble in benzene, benzin, ether, chloroform, carbon 

 disulphide, oil of turpentine, and fat oils. Sulphur is polymorphous ; 

 it crystallizes, from a solution in disulphide of carbon, in octahedrons 

 with a rhombic base ; when, however, liquefied by heat it crystallizes 

 in six-sided prisms, and is obtained as a brown, amorphous substance 

 by pouring melted sulphur into cold water. 



Sulphur melts at 115 C. (239 F.) to an amber-colored liquid, 

 which is fluid as water ; increasing the heat gradually, it becomes 

 brown and thick, and at about 200 C. (392 F.) it is so tenacious 

 that it scarcely flows ; when heated still further the sulphur again 

 becomes tliiji- and liquid, and, finally, boilfr ai a temperature of about 

 440 C. (824- 1\). ' 



In its 5 chemical pr0,pe*rties, aalphu;, i ^semj^s oxygen, being like 

 this element bivalent; a^d. supporting, ,wh.eix ia the form of vapor, 

 the combustion of many substances, especially of metals. Many 

 compounds of oxygen and sulphur show an analogous composition, 

 as for instance H 2 O and H 2 S, CO 2 and CS 2 , CuO and CuS. 



Crude sulphur is that obtained from the localities where it is 

 found. It contains generally from 2 to 4 per cent, of earthy im- 

 purities. Melted sulphur poured into round moulds is known as roll- 

 sulphur or brimstone. 



Sublimed sulphur, Sulphur sublimatum (Flowers of sulphur). 

 Obtained by heating sulphur to the boiling-point in suitable vessels, 

 and passing the vapor into large chambers, where it deposits in the 

 form of a powder, composed of small crystals. 



