CHLORINE. 45 



reversed so as to have one part of silicic acid with three of potash, 

 we have a soluble silicate of potash called liquor stlicum, or liquor 

 of flints, 



CHLORINE. 



Chlorine, along with iodine, bromine, and fluorine, forms a group 

 of simple bodies whose chemical habitudes are remarkably similar. 



Chlorine exists abundantly in nature as an ingredient in common 

 salt It was discovered, in 1774, by Scheele, and by him called 

 dephlogisticated marine acid. The French chemists named it oxy^ 

 muriatic acid, from an opinion that it consisted of muriatic acid 

 and oxyaen. In 1809, Davy discovered its true nature, and gave 

 to it the name of cldorine, from a Greek word signifying greenish- 

 yellow Prepared by the action of hydrochloric acid on peroxide ot 

 manganese, with the aid of heat; chlorine is set free, and water and 

 a chloride of manganese are formed, thus: 



/ Chlorine Chlorine. 



\ Hvdroffen 



2 Hydrochloric acid. I Chlorine ^--.^^^^ 



\ ''^oJyl^n^^^S Water. 

 Peroxide of Manganese, j ^^Y/--— ^^^ Chloride of Manganese. 



Prop —A yellowish-green gas, irrespirable, exciting strong spasms 

 of the glottis ;-sp. gr. 2-47 ;- water at 60° absorbs twice its volume. 

 It is best collected by conducting it by means of a tube, into the bot- 

 tom of tall receivers, the air being thereby displaced. Ihe watery 

 solution, on being exposed to the light, is slowly changed into chloro- 

 hvdric acid, oxygen bein^ set free. When moist chlorine is exposed 

 to a cold of 32° yellow crystals are formed, being a compound ot 

 chlorine and water. Chlorine is condensed into a liquid by a pres- 

 sure of four atmospheres. It is a non-combustible, but a supporter 

 of combustion; a lighted taper burns in it for a short time, but 

 several of the metals, as antimony, tin, copper, and arsenic ake 

 fire spontaneously when presented to it, in a finely divided state 

 In these cases, a chloride of the metal is formed. The stronges 

 affinity of chlorine is for hydrogen: it is in consequence of this that 

 it acts so powerfully as a bleaching agent, water >eing always 

 decomposed in the process, the hydrogen uniting with the chlorine 

 to form chlorohydric acid, and the oxygen which is set free bemg the 

 real decolorizing agent. mi. u * * * r „ 



Chlorine is also useful as a disi7ifecting agent. The best test for 

 chlorine is a soluble salt of silver ;— a white insoluble chloride of 



silver is formed. _ ,, , 7 7 • j i? 



The non-acid compounds of chlorine are called chlorides.— \ho^.=^ 



3 . Symb. CI. 



