The preparation of the apparatus for a titration is crucial to ensure accuracy and reliability of results.
If glassware is dirty, or greasy, some droplets of water or solution are left behind. These droplet will, nevertheless, have been counted as added!

1. Burette:

The technician will have flushed the burette out with tap water, after rinsing it with a detergent. This is what you should do.

• Rinse with distilled water.
  Fill a small portion of the burette with distilled water, close the stopcock, and then shake and rotate the burette to ensure all inner surfaces are rinsed. Drain the water through the stopcock.

• Rinse with the titrant and repeat twice more.
  Fill the burette about one-quarter full with the titrant solution. Rotate and tilt the burette to rinse the entire inner surface. Drain the solution through the stopcock, ensuring the burette tip is also rinsed. 

2. Pipette:

• The technician will have rinsed this in the same manner as for the burette.

• Rinsing with Distilled Water: Draw distilled or deionized water into the pipette using a pipette filler, and then drain it out, ensuring that the inner surface gets a good rinse.

• Rinsing with Solution to be Titrated: Draw up a portion of the solution to be titrated into the pipette and then drain it out. Do this at least twice more to ensure the pipette is well-rinsed with the solution.

3. Conical Flask:

• Cleaning: Clean the flask with detergent and a brush, if necessary, and then rinse several times with tap water.

• Rinsing with Distilled Water: Rinse the flask a few times with distilled water and then once with deionised water.
  Tap water has chemicals dissolved in it, but distilled water doesn’t.

• Never rinse with the solution (analyte).
   Doing this would leave the flask wet with the solution and that would make the titre slight higher than it should be.
  Rinsing it with deionised water leaves no ions that will react with the titrant.

Final Notes:

• Always ensure that all apparatus are free from water droplets after rinsing. Any remaining droplets can dilute the solutions and affect the accuracy of the titration.

• The rinsing procedure ensures that any contaminants or residual solutions from previous experiments are removed and that the solutions used in the titration only come in contact with the solutions they’re intended to interact with.

By diligently preparing your apparatus, you can ensure the reliability of your titration results and reduce potential sources of error.