SPECIAL TESTS 17 



mine give the copper ferrocyanide reaction when placed in an acidulated solution of 

 potassium ferrocyanide. 



The following table from the work by Koenig gives the relative 

 sensitiveness of the tests above described: 1 



9. Making Analytical Reports 



The methods of micro-analysts, whether in private, commercial 

 or government laboratories, should be uniform. Much could be 



1 The comparative degree of sensitiveness of the different chemical compounds 

 concerned in the color reactions above described and tabulated is indicated by the 

 number of cubic centimeters in which i gram of the substance in solution is 

 still appreciable. The actual limit, determined experimentally, is indicated in 

 terms of milligrams, that is o.ooi mg., represented by jug. Expressing the com- 

 parative sensitiveness (CS) in a formula we have 



_ jug limit molecular weights 



amount limit combination valency 

 or to give the example for boron, we have 



CS = 



o.oooo i 59 

 0.00000006 3 



33 3 ooo. 



