Laboratory Glassware Borosilicate Glass Burette with Different Size

The main part of the buret is made of glass tube with uniform inner diameter and accurate scale. The lower end is connected with a glass cock or latex tube containing glass beads to control the liquid flow rate, and the bottom end is connected with a sharp glass tube. The burette with the glass cock at the lower end is called an acid burette, which is often used to measure the volume of the non strong alkaline dilute solution dripped. It is not suitable to contain alkaline solution, because the alkaline solution can corrode the glass for a long time, causing the cock to be unable to rotate.

The volume of buret is not completely consistent with its marked volume, so it must be calibrated in analytical work requiring high accuracy. Because glass has the characteristics of thermal expansion and cold contraction, the volume of buret is different at different temperatures. During calibration, a common temperature value must be specified, which is the standard temperature. The international standard temperature of glass containers is 20 ℃, that is, the volume of glass containers is calibrated to the actual volume at 20 ℃ during calibration.