a.-burette
b.-conical flask
c.-pipette
d.-drops on end of pipette or burette
2007-09-01 14:42:55 · 2 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
In order to minimise contamination.
a.b.c. Rinse through and fully discharge with the reacting chemical, and then load up with with a new charge of the reactant chemical.
d.Drops on the end of pipette/burette. Having rinsed through with reacting chemical discharge some of the chemical through the valve, and back rinse discharge through the open end. The drops are meant to remain there. Burettes and pipettes are designed to hold these drops at the end.
2007-09-04 08:56:15 · answer #1 · answered by lenpol7 7 · 0⤊ 0⤋
a -c : Triple rinse the apparatus with the solution to be filled. Empty through the preferred method (aspiration or force).
d- the drops on the end or a pipette or burette during a titration can be rinsed off using a small amount of water from a squeeze bottle.. often times this drop is the minute quantity that will drive the titration to its end point... whereas, an additional drop will be too much....
2007-09-08 08:23:27 · answer #2 · answered by carasmom 2 · 0⤊ 0⤋