IN CHEMISTRY. 11$ 



5. What is the glassy slag so plentiful about a furnace ? * 



A silicate of lime or some other base contained in the 

 ore. 



Ordinary Slag from Blast Furnace (Bloxani). 



Silica 43.07 



Alumina 14-85 



Lime 28.92 



Magnesia 5.87 



Oxide of iron 2.53 



Oxide of manganese -. 1-37 



Potash 1.84 



Sulphide of calcium 1.90 



Phosphoric acid trace 



100.35 



6. State the formula of nitre, saleratus, carbonate and 

 bicarbonate of soda, plaster, pearlash, saltpetre, plaster of 

 Paris, gypsum, carbonate and bicarbonate of potash, sal-soda* 

 and soda. 



Nitre, saltpetre KNO 3 . 



Saleratus, pearlash HKCO S . 



Carbonate of soda, sal-soda. Na a CO 3 . 



Bicarbonate of soda, "soda".... HNaCO 3 . 



Plaster, gypsum CaSO 4 ,2H s O. 



Plaster of Paris CaSO. 



7. Explain how ammonium carbonate is formed in the 

 process of making coal-gas. 



Nitrogen exists in small quantities in coal, and when 

 that is distilled at a high temperature, the elements in 

 their nascent state combine to form this compound. 



* The slag is commonly employed for road-making in the neighborhood of 

 the iron-works. Some attempts have been made to turn the slag to account 

 by employing it as a manure for soils deficient in potash, of which it will be 

 seen that the above slag contains nearly s \jth of its weight, in a form which 

 would be easily rendered available for plants by the combined action of air 

 and moisture. When the slag is run into water, or blown into a frothy con- 

 dition by the blast, it resembles pumice-stone, and is easily ground to a pow- 

 der fit for applying to the soil. 



