Back titration is also titration. It is called back titration because it is not carried out with the solution whose concentration is required to be known (analyte) as in the case of normal or forward titration, but with the excess volume of reactant which has been left over after completing reaction with the analyte.
What is back titration give an example?
BACK TITRATION Back titration is a process in which the excess of a standard solution used to consume an analyte is determined by titration with a second standard solution. Example: Determination of acetylsalicylic acid in aspirin. Sometime direct titration of an analyte with a reagent is not FEASIBLE.
What is blank and back titration?
In a back titration, titrants react directly with the analyte. In a direct titration, titrants react directly with the analyte. In a back titration, a known excess of reagent that reacts with the analyte is used. The excess is then measured with a second titrant.
Why are back titrations used?
Back titrations are mainly used in the following cases: if the analyte is volatile (e.g., NH3) or an insoluble salt (e.g., Li2CO3) if the reaction between analyte A and titrant T is too slow for a practical direct titration.
What are the 4 types of titration?
- Acid-base Titrations.
- Redox Titrations.
- Precipitation Titrations.
- Complexometric Titrations.
What is difference between titration and back titration?
The key difference between titration and back titration is that in a titration, we usually add a chemically equal amount of standard solution to the analyte whereas, in a back titration, we add an excess amount of standard solution to the analyte.
How do you do a back titration step by step?
5 Simple Steps in Back Titration Calculations: Determine the amount of C required in the titration. Using stoichiometry, find the amount of A that reacted with C in the titration. Note that amount of A that reacted with C in the titration = amount of A that did not react with B in the earlier reaction.
How do you answer back titration questions?
Is iodometric titration a back titration?
This back titration is still an iodimetric titration, since it is based on the reaction of analyte with aqueous iodine; however, using a back titration allows us to use the same titrant (sodium thiosulfate) as we use in the iodometric analysis of hydrogen peroxide.
What are the types of EDTA titration?
Types of titration with EDTA Direct titration: the cations are titrated directly with standard solution EDTA using eriochrome black T as the indicator. Back titration: a known excess of standard solution EDTA is added to the solution containing the analyte.
How do you read a back titration?
What is main titration?
Titration which is also known as titrimetry is a chemical qualitative analysis technique that is used to calculate the concentration of a given analyte in a mixture. Titration is an important technique in the field of analytical chemistry and is sometimes referred to as volumetric analysis also.
Why phenolphthalein is used in back titration?
This type of reaction occurs at a high rate and thus produces an end-point which is abrupt and easily seen. The titration curve for a strong acid with a strong alkali shows that the equivalence point occurs at pH 7. This means that the indicator phenolphthalein can be used.
Where is EDTA used in titration?
The most common indicators in complexometric titrations are organic dyes which function by forming a colored complex with the metal ion being titrated. During the reaction, EDTA replaces the indicator to form a more stable complex with metal and when the reaction is completed the change for the color is observed.
What is the titration formula?
Use the titration formula. If the titrant and analyte have a 1:1 mole ratio, the formula is molarity (M) of the acid x volume (V) of the acid = molarity (M) of the base x volume (V) of the base. (Molarity is the concentration of a solution expressed as the number of moles of solute per litre of solution.)
Why KMnO4 is a self indicator?
KMnO4 Solution is a self indicator because it is a powerful oxidising agent. When sulphuric acid is present in the KMnO4 solution, it is oxidised to sulphuric acid. This change in colour is used to indicate the endpoint of the solution.
What is end point in titration?
end point: the point during a titration when an indicator shows that the amount of reactant necessary for a complete reaction has been added to a solution.
How is back titration used in real life?
For instance, a food processing company might use titration to calculate the precise amount of salt in a particular foodstuff. It can also be used to determine the concentration of vitamin C or vitamin E additives in foods.
Who discovered back titration?
In 1828, the French chemist Joseph Louis Gay-Lussac first used titre as a verb (titrer), meaning “to determine the concentration of a substance in a given sample”. Volumetric analysis originated in late 18th-century France.
What is black titration?
A blank titration is carried out by titrating a fixed and known concentration of titrant into a solvent with zero analyte. The only difference from the regular titration is the absence of analyte.
What is titration analysis?
Titration, also known as titrimetry, is a common laboratory method of quantitative chemical analysis that is used to determine the unknown concentration of an identified analyte (Medwick and Kirschner, 2010). Since volume measurements play a key role in titration, it is also known as volumetric analysis.
What is meant by iodimetry?
iodometry. / (ˌaɪəˈdɒmɪtrɪ) / noun. chem a procedure used in volumetric analysis for determining the quantity of substance present that contains, liberates, or reacts with iodine.
What is iodometric titration?
The iodometric titration is a general method to determine the concentration of an oxidising agent in solution. In an iodometric titration, a starch solution is used as an indicator since it can absorb the I 2 that is released.
Why is EDTA pH dependent?
EDTA Formation Constants By Le Chatelier’s Principle, the complex will dissociate at low pH’s, and it will be more stable at high pH’s. EDTA titrations are therefore pH dependent and analyte solutions must be buffered to the optimum pH.
What is the principle of EDTA?
EDTA is Ethylene diamine tetra acetic acid. It dissolves in water with great difficulty, but its disodium salt dissolve in water quickly & completely It is hexa dentate ligend. It binds the metal ions in water to give stable chelate complex. Hence it is called as complexometric titration method.