378 HISTORICAL INTRODUCTION TO CHEMISTRY CHAP. 

 The formula of the salt is deduced as follows : 



Potassium 



POTASSIUM CHLORATE = 1*2846 

 1-2846 



= 39'i 

 = 0-0329 

 = i 



Formula KC1O 3 . 



3. Chalk. As Berzelius was not able to obtain pure 

 metallic calcium, he could not determine the composition 

 of lime by direct oxidation ; an indirect method of analysis 

 was therefore adopted : 



(1) 10 grams of chalk when ignited gave 5*64 grams of 

 lime and 4-36 grams of carbonic anhydride containing 

 28-4% of carbon. 



(2) 10 grams of chalk dissolved in muriatic acid gave 

 10-96 grams of fused muriate of lime (calcium chloride). 



(3) 3' QI grams of this fused muriate, when dissolved and 

 precipitated with silver nitrate, gave 775 grams of " horn- 

 silver" (fused silver chloride), containing 7 5 '3% of silver and 

 therefore 24-7% chlorine (Klassiker, XXXV. 77). 



From these experiments it followed 



(4) That 10 grams of chalk contained 0-284 x 4'36 = 1'238 

 grams of carbon, united with 4*36- 1*238 = 3*122 grams of 

 oxygen to form carbonic anhydride. 



(5) That 3-01 grams of muriate of lime contained 0*247 x 

 7-75 = 1*914 grams of chlorine united with 3-01-1*914 = 

 1-096 grams of calcium ; therefore the 10-96 grams of 

 muriate of lime derived from 10 grams of chalk contained 



I0 ' 96 x 1*096 = 3*99 grams si calcium. 

 3*01 



(6) That the 5*64 grams of lime obtained by igniting 10 

 grams of chalk contained this 3*99 grams of metal united 

 with 5*64-3*99 = 1'65 grams of oxygen. 



