Acid burette and burette why different structure
The basic buret cannot use frosted glass, like a night can produce sodium silicate, lead glass cock is stuck and can not rotate. With smooth glass beads with rubber tube, you can play a sealing role, the use of a little skill, pinch the rubber tube, in the upper part of the glass bead force, resulting in a gap, let the liquid drop out. If pinch in the lower half, it will lead to the lower end of the glass tube bubble, the amount is not accurate. Burette after use must be washed with water.
A frosted glass knob with a Teflon plug instead of acid burette, the high price of some, but not afraid of corrosion lye, a general acid burette.
Acid burette can be used frosted glass cock, convenient use, good sealing performance.
The reason is that the glass is acid resistant, but it is caustic.
