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Why ist necessary to rinse the clean burette before filling it with the unstandardised sodium hydroxide solution?
Wiki User
∙ 13y ago
It is a rule of safety in chemistry: to remove any micro-drops of water from the pipette.
Wiki User
∙ 13y ago
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Why is it necessary to rinse the burette with sodium hydroxide before you completely fill it up?
Before a burette is used, it needs to be cleaned. During the cleaning process, usually, water is introduced into the burette. Be the water clean or not, if the burette is then used without rinsing it with the solution that it is going to be filled with, the result of that analytical exercise will not be precise and accurate. The reason is that water residue in the burette would dillute the solution when it's filled in the burette which would make it impossible to determine the exact concentration of the solution moved by the burette. By rinsing and re-rinsing the burette several times with the solution it is going to be filled with, residue water from the cleaning process would be successfully removed from the burette as are other leftover substances from the cleaning process. This practice is quite important as basic analytical technique.
When filling the burette why must the solution fill the tip of the burette below the burette tap-and contain no air bubbles?
Because we need to know the exact volume of the solution (and so the amount of the titrant).
What are the function of base burette in laboratory?
Base burettes are used for base titrants. Basically this is used in titrations where the analyte is an acid.
Which piece of apparatus is used to add dilute nitric acid to potassium hydroxide?
a burette
What is a titration?
A titration is the use of carefully measured amounts of a known solution to determine the concentration of another. They often involve acid-base neutralisation or oxidation-reduction reactions (examples would be sodium hydroxide with hydrochloric acid, or permanganate with an iron solution). The main part of the system is the burette, a large graded tube with a controllable variable nozzle at its end. This nozzle is used to add different amounts with great precision to the solution being tested, so that an exact reading can be made - if done correctly, the titration's accuracy is limited only by the scale on the burette. A sample of the test solution (collected using a pipette with a known volume and high degree of accuracy; the sample is called an aliquot) is placed in a container, usually a conical flask, under the burette. The burette is filled with known solution, i.e. one where the concentration is know to another high degree of accuracy. The two are mixed slowly and allowed to react - for acid-base titrations an indicator will be added to the flask, for redox the solution which will change colour is put in the burette. This is continued slowly until the solution will barely react with that from the burette. At this point the amount of solution taken from the burette is recorded. Ideally, the next slightest drop of burette solution will cause a change in colour of the solution that does not change at all. If not, the new recording is made and the last step repeated. This amount is a titre. The whole experiment is repeated several times. The data is collected and averaged out. From this, an amount of known solution used, an amount of tested solutio used and eventually a concentration can be found.
Why isn't sodium hydroxide not normally placed in a burette?
Sodium Hydroxide isn't placed in a burette because it is a solid, and burettes hold liquids.
Why is it advisable to remove sodium hydroxide from the burette as soon as possible after titration?
Sodium hydroxide, particularly highly concentrated sodium hydroxide, can dissolve glass if left sitting long enough. Therefore, if you leave the sodium hydroxide in the burette after finishing your titration, you could increase the volume inside the burette from the glass being dissolved from the inside out. This would make the burette measure the titration volume inaccurately and would invalidate the results of future titrations done with this instrument.
Why is it necessary to rinse the burette with sodium hydroxide before you completely fill it up?
Before a burette is used, it needs to be cleaned. During the cleaning process, usually, water is introduced into the burette. Be the water clean or not, if the burette is then used without rinsing it with the solution that it is going to be filled with, the result of that analytical exercise will not be precise and accurate. The reason is that water residue in the burette would dillute the solution when it's filled in the burette which would make it impossible to determine the exact concentration of the solution moved by the burette. By rinsing and re-rinsing the burette several times with the solution it is going to be filled with, residue water from the cleaning process would be successfully removed from the burette as are other leftover substances from the cleaning process. This practice is quite important as basic analytical technique.
When filling the burette why must the solution fill the tip of the burette below the burette tap-and contain no air bubbles?
Because we need to know the exact volume of the solution (and so the amount of the titrant).
What are the function of base burette in laboratory?
Base burettes are used for base titrants. Basically this is used in titrations where the analyte is an acid.
Which piece of apparatus is used to add dilute nitric acid to potassium hydroxide?
a burette
How do you clean pipette?
First remove all the solid particles from the burette using a scrubber. Then wash the burette with tap water followed by distilled water thoroughly (even the nozzle). Then wash the burette with the solution to be used in the burette.
What is a titration?
A titration is the use of carefully measured amounts of a known solution to determine the concentration of another. They often involve acid-base neutralisation or oxidation-reduction reactions (examples would be sodium hydroxide with hydrochloric acid, or permanganate with an iron solution). The main part of the system is the burette, a large graded tube with a controllable variable nozzle at its end. This nozzle is used to add different amounts with great precision to the solution being tested, so that an exact reading can be made - if done correctly, the titration's accuracy is limited only by the scale on the burette. A sample of the test solution (collected using a pipette with a known volume and high degree of accuracy; the sample is called an aliquot) is placed in a container, usually a conical flask, under the burette. The burette is filled with known solution, i.e. one where the concentration is know to another high degree of accuracy. The two are mixed slowly and allowed to react - for acid-base titrations an indicator will be added to the flask, for redox the solution which will change colour is put in the burette. This is continued slowly until the solution will barely react with that from the burette. At this point the amount of solution taken from the burette is recorded. Ideally, the next slightest drop of burette solution will cause a change in colour of the solution that does not change at all. If not, the new recording is made and the last step repeated. This amount is a titre. The whole experiment is repeated several times. The data is collected and averaged out. From this, an amount of known solution used, an amount of tested solutio used and eventually a concentration can be found.
Why the burette and the pipette are each rinsed with distilled water and finally rinsed with some of the solution that will be measured or transferred?
These are conditions necessary to avoid contamination or any other modification of the reagents.
Why the burette and pipette are each rinsed with distilled water and finally rinsed with some of the solution that will be measured or transfer?
These are conditions necessary to avoid contamination or any other modification of the reagents.
Why it is preferred to take acid in burette during acid base titration?
The burette can be filled with either acid or base. The acid will go into the burette only if you want to titrate a base , i.e. you don't know the concentration of the base and want to find out. The solution of known concentration goes always into the burette (in order to be able to measure the volume taken to complete the reaction) and so if you wanted to find out the concentration of an acid you would put the base into the burette.
Which meniscus is to be seen in the burette containing kmno4 solution and why?
upper meniscus...
