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All glassware should be washed with water and then with soap and brushed by the brush tubes, then rinsed again with water. Then last rinsed with aquadeast. Burette as a place for reagent or standard solutions or titrator should be rinsed 3 times with a standard solution or titrator. Then weigh the sample or titrant into the weighing bottle by using the analytical balance (see how to use analytical balance article). For example, the sample is 1.4536 grams. Then add distilled water and mix with stir bar until everything is dissolved.
Take a 250 ml volumetric flask and then enter the solution in the weighing bottle to the volumetric flask by following the article how the use volumetric flask. Enter the standard solution into the burette using a beaker 100 ml by following the article how to use Burette, then take 25 ml solution from the volumetric flask using graduated pipette, by following the article on how to use the graduated pipette.
Put 25 ml the solution in the graduated pipette to 250 ml Erlenmeyer, add 2 drops of indicator solution. Indicator solution is a solution containing a substance that changes color when the endpoint is reached, but the substance did not participate in the reaction. Indicator solution varies depending on each reagent and the reaction. As an example for acid-base reaction is used phenolpthalein indicator. The Acid-base reaction of reactions that occur in between a strong acid and a strong base. If the solution that is in the burette one of strong acids or strong bases.
Then do titration with a standard solution from the burette. Open the tap burette so the solution drips little by little. Shake Erlenmeyer unidirectional by folloeing the article how the use Erlenmeyer. If the color changes, then close the tap Burette immediately. Not to excess, even if one drops, because the results will not be accurate. Record the volume titrator in Burette that used and calculate the concentration samples or titrant by the formula:
Concentration titrant = Concentration Titrator x Volume Titrator x mol titrant
Volume titrant
Titration using potentiometer easier to do than titration with the glassware manual method. Potentiometri is a method used by a surge in potential energy in the reaction between standard (titrator) and samples (titrant). pH meter can also be used for titration, but only on the reaction acidi-alkalimetry for endpoint was calculated based on the occurrence of a surge in pH the solution. In the event of a potential energy or the pH surges this mean the endpoint was reached and the volume of the standard solution can be calculated. It does not require the indicator solution.
How to do a titration with a potentiometer or pH meter is insert standard solution in a burette by following the article how to use Burette. Then pipette 25 ml of the sample solution or titrant from the volumetric flask using a graduated pipette. Put it in a 100 ml beaker. Place this beaker on a magnetic stirrer and insert a magnetic into it. Stir at the middle speed. Rinse potentiometer electrode or pH meter electrode with distilled water 3 times. Then dip it in solution in a beaker containing that titrant. Be careful with the magnet on the electrode. Because the electrodes can damage or even break.
Record the energy potential or pH that measured. Then drops 5 drops of standard or titrator from the burette. Let stirred by a rotating magnet for 30 seconds, record again the energy potential or pH was measured. Then repeat again until the potential energy or pH surge. It means the endpoint reached. Continue the titration process by adding 1 or 2 ml standard solution from a burette. And still record the energy potential or pH were measured every 5 drops. Plot a graph of the potential energy with burette volume or pH with volume burette. Specify endpoint through this graph. Calculate the concentration samples or titrant by the formula above. If you have finished using electrodes on potentiometer or pH meter, it must rinse with distilled water and put in a buffer solution by following the article on how to use a pH meter.
Autotitrator is an instrument that can automatically perform a titration based on the potentiometri. Autotitrator is the easiest, fastest, and most modern titration. In autotitrator are a bottled as a place to store standard solution or titrator. In the bottle there is a small hose that can be connected into a beaker or cup reaction. There's another bottle as a waste storage of titration results. Autotitrator also accompanied by a small compressor to suck this waste. Electrodes connected to autotitrator and there is a plastic test tube containing buffer solution as a place to store the electrode.
Buttons on autotitrator that the on and off to switch on and off. Start and stop buttons to start and stop the titration process. The number keys to enter the data and the key to run the program or calculate titration process. Button compressor to suck waste titration results. Autotitrator Titration is based on the occurrence of the potential energy surge in reactions that occur. Autotitrator also comes with a magnetic stirrer for stirring the solution. A small printer is also connected with autotitrator to print the results of the titration.
How to use autotitrator that enter a standard solution into standard bottles. Also fill the small hose until full. There must be no air bubbles in the hose. Set parameters at titration program, the input concentration of standard solution or titrator, the weight of the sample is weighed, volume volumetric flask and volume graduated pipette used for sample or titrant. Then take 25 ml of the sample solution with graduated pipette and put in a beaker of 100 ml.
Place this beaker on a magnetic stirrer. Take the electrode and rinse with distilled water. Enter the electrode and standard solution or titrant hose into a beaker of 100 ml. Dip up to 1 cm above the base solution. Then insert a small magnet into a it. Turn on the magnetic stirrer so that the magnet rotates. Set the speed at medium speed. Be careful with the magnet on the electrode. Because the electrodes can damage or even break. Press the start button so the titration starts.
When a surge of energy potential and the titration end point is reached, stop the titration process by pressing the stop button. Or if it is known to estimate the volume that will be used in the titration process, you can set the volume of the standard solution in the titration program. At the time this volume has been reached, then the titration process is automatically terminated. Do not let the titration end, if the endpoint has not been reached. Meanwhile, volume that was set before has been reached and the titration process is automatically terminated, the titration process must be repeated because it has not reached the endpoint. At the time of the titration process is ended, then the printer will automatically print the titrant or sample concentration along with the parameters used. No need to count again manually.
That's part of the tools used in the lab, from manual to modern titration.
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