Your analyte is the sample in which you are looking for a specific chemical quantity. That chemical is your titrand. For example, if you are checking the chloride levels in your local water supply, tap water would be your analyte, and the chlorides would be your titrand. Your titrant is the chemical that you add to your analyte in measured quantities to help you calculate the amount of your titrand. You want enough of your titrant that you can repeat your titration at least 3 times. If you are unsure of how much of your titrant you need, you can look online or consult your lab’s director.
Repeat the rinsing process at least 3 times with water to completely clean your burette. After you’ve rinsed the burette with water, perform the same rinsing process at least 2 times with your analyte.
Repeat the rinsing process at least 3 times with water to completely clean your burette. After you’ve rinsed the burette with water, perform the same rinsing process at least 2 times with your analyte.
If you do not have deionized water, available, tap water will work. However, the distilled water rinse will still be necessary as this lowers the chances of contamination for your analyte.
If you overfill your burette, open the stopcock slightly and let the excess titrant flow out until it reaches the zero mark.
If necessary, rinse the analyte into your beaker or flask, thus making sure all of the analyte is in the beaker. The amount of analyte you need will depend on your experimental design, the types of chemicals, and the titrand you’re trying to find.
Likewise, the amount of color indicator you need will depend on the volume of your analyte. Generally, you will need between 3-5 drops of indicator for 100 mL of analyte.
As with the color indicator, the amount and type of buffer you may need depends on your quantity of analyte and the titrant for which you’re looking. Generally, though, you will add your buffer until it removes the tint imparted by the color indicator. Generally, the buffer solution will be an acid or alkali in a specific, known concentration.
You will leave the stir plate on until your titration is complete. If you do not have a magnetic stir plate, you can agitate the beaker by hand by gently swirling it 4-5 times before placing it under the burette.
If you notice a color change, close the stopcock and allow the agitator to run for 30 seconds. If the color dissipates before the 30-second mark, open the stopcock slightly and continue to add the titrant drop by drop until you get a permanent change. [13] X Research source If you’re not using a magnetic stir plate, close the stopcock once you notice the first flash of color change. Agitate the beaker to see if the color dissipates. If it does, replace the beaker under the burette and continue the titration. If it does not, you’ve reached your endpoint.
When reading the end volume of your burette, make sure your eyes are at the level of the titrant meniscus. Take your reading from the meniscus.
For your burette, fill it with water, open the stopcock, and allow it to drain completely. Repeat this 2-3 times to rinse out the burette. [16] X Research source
Calculations of the concentration should be done to the appropriate number of significant figures. Ask your instructor or lab director if you’re unsure of what these may be.
