CHLORATE OF POTASH.
297
When chlorine gas comes in contact with a solution of carbonate ofpotash, three salts are fonned: chloride of potassium, hypochlorite ofpotash, and bicarbonate of potash.
REAGENTS.
2 eq. Carbonate Potash .... 140“/•2 eq. Carb c .A d . 44-2eq.Carb le . jl eq. Potash . 48-Potash 140 ;1 eq. Oxygen. 8"W eq. Potassium 40'2eq.Chlo- (1 eq. Chlorine 36'"rine . . 72 11 eq. Chlorine 36-
products.p 2 eq. Bicarb te . Potash 184
-7-. leq. Hypochlor*.A d A£ } 1 e< l- H yP och1 "- Poth - 92
In proportion as the quantity of chlorine increases, the bicarbonate be-comes decomposed : carbonic acid is evolved, and a further quantity ofhypochlorite of potash and chloride of potassium is produced.
When the solution is strongly charged with hypochlorite, the actionof the chlorine on the potash is somewhat changed: it abstracts thepotassium from the potash, and thereby forms chloride of potassium,while the oxygen thus set free combines with some hypochlorite ofpotash, and thereby converts it into the chlorate, the greater part of whichcrystallizes.
REAGENTS.
4 eq. Chlorine.144 -
. T 3 i. U , no V4 eq. Potassium. . 160
4 eq. Potash 192 J 4e( J 0xygen . 32 .
products.
-4 eq. Chloride Potassium 304
»1 eq. Chlorate Potash . . 124
The residual liquor contains a little chlorate, and a considerable quantityof hypochlorite of potash and chloride of potassium (Souberain, Phar-macie, t. 2 me . p. 430.)
Properties. —Chlorate of potash crystallizes in nearly rliomboidalplates, the primary form of which is an oblique rhombic prism. Its tasteis cool, and somewhat similar to nitre. When rubbed in the dark itbecomes luminous. 100 parts of water at 32° F. dissolve 3o parts ofchlorate: at 59° F. 6 parts: at 120° F. 19 parts.
Characteristics. —This salt is known to be a chlorate by the follow-ing characters :—When heated, it fuses, gives out oxygen, and is con-verted into chloride of potassium: when thrown on a red-hot coal, itdeflagrates—a property, however, common to several other salts. Sul-phuric acid gives it an orange red colour, evolves the chlorous acid(peroxide of chlorine), known by its yellow colour, and great explosivepower when heated. Rubbed with sulphur or phosphorus it explodesviolently. Mixed with hydrochloric acid and then with water, it forms ableaching liquid. The base of the salt is known by the tests for potash,already mentioned.
Composition.— It is an anhydrous salt.
Chloric Acid. 1 . . . . 76 ... . 61*30 . 61*5083
Potash. 1 . . . . 48 ... . 38*70 . 38*4917
Chlorate of Potash ... 1 .... 124 ... . 100*00 . 100*0000
Impurity. —Chloride of potassium is the usual impurity. This maybe detected by a solution of nitrate of silver producing the white chlorideof silver. The pure chlorate potash produces no obvious change innitrate of silver.