METHODS FOR QUANTITATIVE DETERMINATIONS. 253 



Volumetric methods. The great advantage of volumetric over 

 gravimetric analysis consists chiefly in the rapidity with which these 

 determinations are performed. Unfortunately, volumetric methods 

 cannot be employed to advantage for the estimation of all substances. 



The special apparatus required for volumetric analysis consists of 

 a few flasks, some pipettes, burettes, and a burette-holder. The flasks 

 should have a mark on the neck, indicating a capacity of 100, 250, 

 500, and 1000 c.c. respectively. (See Fig. 31.) 



FIG. 33. 



FIG. 34. 



Mohr's burette and clamp. 



Mohr's burette and holder. 



Of pipettes (Fig. 32) are mostly used those having a capacity of 

 5, 10, 25, and 50 cubic centimeters. 



Of burettes many different forms are used ; in most cases Mohr's 

 burette (Figs. 33 and 34) answers all requirements, but its applica- 



