168 The Phosphates of America. 



igniting the bicarbonate to redness, in water, and make up to one 

 litre. 



NORMAL SULPHURIC ACID. 



Dilute about 30 c.c. of pure sulphuric acid (sp. gr. 1.840) to one 

 litre ; then determine the strength of this solution by titration with 

 normal sodium carbonate, and dilute so as to make one c.c. of the 

 sulphuric acid neutralize one c.c. of the alkali ; after dilution check 

 the strength by another titration. 



DECI-NORMAL OXALIC ACID. 



Dissolve 6.3 grammes of pure, recrystallized oxalic acid, dried 

 between paper, in one litre of water. 



NORMAL HYDROCHLORIC ACID. 



Dilute 181 grammes of the pure acid, of sp. gr. 1.10, to one litre ; 



.N 

 check by titration with silver solution or by sodium carbonate. 



NORMAL NITRIC ACID. 



Take some pure nitric acid and dilute to one litre. The strength 

 of this solution must be ascertained, and the acid diluted accord- 

 ingly. The most exact method of checking the nitric acid is by 

 pure calcium carbonate, one gramme of which requires 20 c.c. of 

 normal acid. 



NORMAL CAUSTIC ALKALI. 



Take about 42 grammes of pure sodium hydrate and dis- 

 solve in 800 c.c. of water ; titrate with any normal acid, and dilute 

 until it corresponds with the acid, volume for volume. NORMAL 

 POTASSIUM HYDRATE may be made in a similar manner. 



NORMAL AMMONIUM HYDRATE 



is made by diluting strong ammonia to the required strength, and 

 checking by titration with normal acid. 



DECI-NORMAL SILVER NITRATE SOLUTION. 



Dissolve 10.8 grammes of pure silver in pure dilute nitric acid,, 

 heat gently, and when dissolved dilute to one litre. If a neutral 

 solution is required, take 17 grammes of pure silver nitrate and 

 dissolve in water to one litre. Of this solution 



