Guide To Using a Burette for Titration

 Titration is a technique used in the life sciences and healthcare industry where the solution of known concentration is used to find out the concentration of the unknown solution. Generally, the known solution (titrant) is added from a titration burette to a fixed amount of unknown solution (analyte) until the completion of the reaction. As the titrant volume is known, it is easier to determine the analyte’s concentration using the titration formula. Often a buffer or pH solution is used to indicate the end of the titration.

Titration is one of the most frequently used quantitative analyses that help researchers develop or analyze chemical compounds. Titration seems like a simple procedure, but if not performed carefully, the integrity of your experiment may be compromised. There are several steps that are involved in the titration process. Each step must be executed with vigilance to obtain the correct result. The following abstract discusses the correct use of burettes.

To fill the burette and allow free flow of solution.

The titration burette correctly measures the amount of liquid allowed to pour into the conical flask. It makes the task of delivering a measured volume of liquid of desired quantity. However, to avoid any mistakes, first, the glass burette must be clamped vertically and ensure the valve is closed at the base. Then, fill the burette using a funnel. You might have to lift the funnel a bit to let the solution flow freely. This strategy helps in the free flow of solutions. On the other hand, in an electronic burette, this step is significantly simplified. An electronic burette is simply mounted on the bottle and it can automatically aspirate the solution from the bottle with the help of a motor, without the requirement of manual intervention.

Conditioning the burette

Before the titration process, it is vital to condition the burette using titrant solution. At the same time, check whether there is a free flow of the solution or not. The best way to condition the Titration Burette is to rinse it well with titrant solution ensuring that the entire surface of it gets perfectly coated. Make sure you drain the solution postconditioning. However, one needs to condition the burette a couple of times. This step ensures that the titrant remains unchanged by a tiny water drop. This step is not required in an electronic burette.

Flush air bubbles

The next step is to flush the air bubble within the burette. When filling the burette, place a waste beaker under the tap and briefly open it as you pour the solution. It flushes out any air bubbles from the burette. Close the tap and fill the burette to the 0 mark. Note the initial reading. Air bubbles within the burette add volume to your initial reading leading to errors. In the case of an electronic burette, this step is again simplified. You may use the in-built purging feature to clear the burette cylinder of any bubbles.  

Performing the titration 

Make sure the top of the burette is below eye level. Lower the burette stand or stand on a stool to reach. Place your left hand around the tap of the burette while with the right hand swirl the conical flask as titrant is added. This step is a crucial one and needs high concentration. Also, the correct titration speed needs to be found. Too slow, the titration process is prolonged, too fast the equivalence point exceeds. When starting the procedure, the titrant can run into the flask in a continuous stream. As the indicator color change becomes a little persistent, switch to adding single drops. When desired indicator color persists for 10 seconds after mixing, the experiment reaches the endpoint. Now note the final reading. In case of an electronic burette, you have the option of electronically dispensing the titration at different speeds, including dropwise dispensing. The burette control panel displays the reading in real-time as the titrant is dispensed. You may note the final reading on the panel after the color change happens or the titration experiment is complete.

As you may notice, there are various steps involved in the titration experiment, and one error, the entire experiment fails. Microlit’s electronic titration burette simplifies the entire process and minimizes the risks of errors that commonly occur in titration experiments using conventional glass burettes. 

For more information on the product, visit https://www.microlit.us/product-category/burette/.