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Sources of errors in Titration experiment |
What is titration?
Titration is the slowly addition of one solution of a known concentration which is known as a titrant to a known volume of another solution of unknown concentration until the reaction reaches neutralization, which is often showed by a change in colour of solution.The solution known the titrant must satisfy the required requirements to be a primary or secondary standard. In a long term, Titration is a method to determine the concentration of an unknown solution.
Types of Titration-
There are several types of Titration but here we will see only the important types.
1) ACID-BASE TITRATION:
Acid- base Titration are majorly helpful to find the amount of a known acidic or basic compounds through acid base reactions. The analyte also called as titrand is the solution with an unknown molarity. The reagent titrant is the solution with a known molarity that will react with the analyte.
2) BACK TITRATION:
A back titration is a titration process where the concentration of an analyte is determined by reacting it with a known amount of large amount of reagent. The remaining excess reagent is then tritrated with another one reagent.
3) VOLUMETRIC TITRATION:
Volume measurements is the very important in titration, it is also called as volumetric analysis. A reagent, known as the titrant or titrator is produced as a standard solution. A known concentration and volume of titrant reacts with a solution of analyte or titrand to determine concentration.
What are titrate and titrant?
Titrant - Regent solution added from burette in small portions, still the reaction is complete,
Titrant - The solution taken in the conical flask or desirable container.
Why is titration important in chemistry?
Titration is a Quantitative Volumetric Analysis process or technique, that is helpful to determine the exact strength of solutions by estimating their Molarity or Normality while titrating them with a Standardised solution that means the solution of known concentration. The dilution formula used is shown below-
M1V1=M2V2 or N1V1=N2V2
Using this data one can calculate its strength too
Strength =N X E
where N is Known as the normality of solution and E is called as equivalent mass of the solute.
We can therefore assay a specific chemical substance in solution or mixtures. This technique is employed in pharmaceuticals or drug analysis , chemical analysis and so on.
Titration is a silent sensitive analytical process that lets us determine an unknown concentration of a chemical in solution by introducing a known concentration of another chemical. Many factors can cause errors in titration findings, containing misreading volumes, mistaken concentration values or faulty technique.
Errors and Precautions in Titration:
What are some sources of errors in titration?
There are many different sources of errors in Titration Experiment to occurs in due course of titration. It may be either of end point error, misreading volumes, concentrations, faulty use of equipment, contaminated glass ware, etc and so on. Some of major errors are shown below-
1) There is the mistakes during the judging the color of the indicator near the end point this is probably the most common one. Many times the colour change is delicate and slow and not everyone have the same sensitivity to colours.2) Transferring of two different solutions using a same pipette and not washing pipette with distilled water in between this process during experiment creates an errors.
3) Using of incorrect concentration titrant we use may have different concentration than expected. This can be due to wrong standardization, error in copying the concentration, contamination of the bottle content, titrant decomposition, solution being kept in open bottle and partially evaporated and so on.
4) Uncleaned or dirty equipments / apparatus.
5) Cleaning burette or pipette with incorrect solution, if the burette or pipette is not dry before use, it has to be rinsed with the solution that will be transferred. Using just distilled water for rinsing will mean transferred solution is slightly diluted. Obviosuly, it is important only when transferring sample, titrant or stoichiometric reagents used for back titration.
6) Transferring large amount of volume of liquid by blowing pipette for example, or by wrongly leveling meniscus with the point or mark on the single volume pipette.
7) Leaking burette sometimes burettes leak slowly enough to allow titration, but will loose many tenths of milliliter if left for several minutes after titrant level has been set to zero and before titration initiated.
8) Titrating at incorrect temperature and wrong pH value as different indicators are quite sensitive.
9) Other human or apparatus errors can also creep in. Human error contains using choice of the incorrect reagents or using the incorrect amount of indicator. Equipment error typically is in the burette, that can Increasing leaks over time. Even a small loss of fluid will impact on the results of the titration.
How do I get my Titration accurate every time to avoid errors?
Do not hurry-
One of the major mistakes I find myself creating while titrating are hurrying too much and adding too much and not getting the correct “light pink” in case of phenolphthalein, of course. A counter measure is to get a pilot reading first. A pilot reading is a test reading in which we titrate relatively speedy carelessly, not too carelessly though to get a general idea about the range in which the endpoint lies. On later observations, we can directly or quickly up to 1 to 2 ml less than the pilot reading and then go drop wise slowly.
Use dilute solutions-
If we considered completely the accuracy of the experiment, using more dilute solutions in the burette gives us lesser error.
Some techniques that can help you rise in accuracy in titration experiments-
1) Examine your overall apparatus especially calibrated glass equipment like burette. There are different types of stop crock create sure these stopcock are working correctly and there should be no leakage because non-calibrated reagent drop can creates blunders in calculation.3) Measuring techniques: |
Measuring methods are very important in chemical titration experiments. whenever we are going to measure any solvent make sure it always read meniscus at the eye level that shown as below images. There are some solvents that behave like concave and convex so measure respectively a and test tube.
4) Air bubbles:
Don't ignore air bubbles while measuring any solvent. If we observe air bubble just wash out some solvent and make sure that air bubble is washed out.
5) Conversion and dilution :
The conversion like liter to milliliter. Vigilant about conversion. Most of the reagents prepare in lab rotary scale which is in liter and while performing its convert into milliters.
Moles : grams/ molar mass.
Molarity: moles/ volume
This is basic formula helps you out while doing unknown dilutions.
Va * Ma/Na= Vb *Mb/Nb ; where
Ma is the volume of acid used.
Na is the concentration of acid
Na is the Number of moles of acid in balanced equation for reaction.
Vb is the Volume of base used.
Mb is the concentration of base.
Na is Number of moles of base in balanced equation for reaction.
some times many teachers used C1V1= C2V2
or M1V1= M2V2 formula as well.
What are the uses of titration in industry?
Titration is a very useful procedure in determining proportion of chemicals in a solution.
A) Waste Water Analysis -
C) Food Industry:
D) Wine Industry:
E) Environmental Factors:
| So, this are the all deatails information about Titration experiment in Chemistry especially. That is main point is Sources of errors in Titration Experiments, Precautions for Titration etc. |
