- Why is it important to fill the space below the tap in a burette?
- Does the amount of indicator affect titration?
- What happens if you use too much indicator?
- Does phenolphthalein turn pink in acid or base?
- Why does phenolphthalein turn pink then clear?
- What can affect titration results?
- Why do we stop a titration when the indicator changes color?
- What happens if you use the wrong indicator in a titration?
- Why is it important to not add more than 3 drops of indicator?
- What happens when we add acid to phenolphthalein indicator?
- Why doesn’t the indicator affect the titration results?
- What are the possible sources of error in titration?
Why is it important to fill the space below the tap in a burette?
Filling the burette this way is also useful because it means the space under the tap is also filled with liquid.
This is important, as the burette is calibrated to include this volume.
When the end point is reached, the burette tap is closed, and the volume of alkali added is recorded..
Does the amount of indicator affect titration?
The indicator itself is either a weak acid or a weak base. Adding too much indicator will force your titration to significantly include the indicator an an interfering analyte component competing with your titrant against the acid or base which you are expecting to measure.
What happens if you use too much indicator?
If a large amount of indicator is used, the indicator will effect the final pH, lowering the accuracy of the experiment.
Does phenolphthalein turn pink in acid or base?
Phenolphthalein is often used as an indicator in acid–base titrations. For this application, it turns colorless in acidic solutions and pink in basic solutions. It belongs to the class of dyes known as phthalein dyes.
Why does phenolphthalein turn pink then clear?
Phenolphthalein is a weak acid and is colorless in solution although its ion is pink. … Adding hydroxide ions (OH-, as found in bases) will change the phenolphthalein into its ion and turn the solution pink.
What can affect titration results?
The Titration process is influenced by the following factors:Measuring method.Instrument (instrument uncertainty/abrasion of the burette)Electrodes (electrode uncertainty/alteration of electrodes)Handling.Balance (weighing error)Temperature.More items…
Why do we stop a titration when the indicator changes color?
When the color stops to change, we are well past the steep part of the curve and we have added significant excess of the base to the solution. We should end titration at the very first sign of the color change.
What happens if you use the wrong indicator in a titration?
In contrast, using the wrong indicator for a titration of a weak acid or a weak base can result in relatively large errors, as illustrated in Figure 17.3. … In contrast, methyl red begins to change from red to yellow around pH 5, which is near the midpoint of the acetic acid titration, not the equivalence point.
Why is it important to not add more than 3 drops of indicator?
It’s important to use only a few drops of indicator because if more of the indicator is used into the solution, it could change the pH since the indicator is a weak acid itself. We would ideal only want one or two drops because this would allow for the most accurate color change with the different salts.
What happens when we add acid to phenolphthalein indicator?
Phenolphthalein is an acid indicator,means when we add water (pH 7) to it,it ionises giving a pink colour. … When we add phenolphthalein to acid due to common ion effect concentration increases. It becomes more than that of concentration. So it appears colourless.
Why doesn’t the indicator affect the titration results?
In all titrations, the amount of indicator added to the solution to be titrated is just a small amount. … Since titration is not as sensitive as any instrumental methods, the low volume of the titrant consumed by the indicator is not that big of a deal because it would not be reflected on the final volume.
What are the possible sources of error in titration?
Several factors can cause errors in titration findings, including misreading volumes, mistaken concentration values or faulty technique. Care must be taken as the solution of the known concentration is introduced into a specific volume of the unknown through laboratory glassware such as a burette or pipette.