302 



ELEMENTARY GENERAL SCIENCE 



CHAP. 



The following salts are thus obtained : potassium 

 potassium nitrate, potassium chloride, sodium sulphate, sodium 

 nitrate, and sodium chloride. All are white solids, two of them 

 being important commercial products, viz., potassium nitrate, 

 which is known as nitre or saltpetre, and sodium chloride, which 

 is common salt. 



Quantitative Nature of the Reactions. It will be also 

 necessary to examine these reactions quantitatively. 



EXPT. 30G. Weigh out about 40 grams of pure caustic soda 

 and about 50 grams of pure caustic potash. (To do this a 

 weighed and corked flask may lie used, since these compounds 

 rapidly absorb moisture from the air.) Dissolve eacli in 



1 234 



FIG. 139. Volumetric Apparatus. 

 1. Measuring Flasks. 2. Graduated Jar. 3. Burette. 4. Pipette. 



distilled water and make up the solution to exactly 1 litre, 

 using a measuring flask for this purpose. Make up also dilute 

 solutions of sulphuric, nitric, and hydrochloric acids ; about 

 1 volume of the strong laboratory acid to 20 volumes of water. 



