Top titration interview questions often focus on the fundamentals, such as defining titration, distinguishing between the equivalence point and the end point, and explaining various titration types—including acid–base, redox, and complexometric methods. Candidates may also be asked about the principles behind specialised techniques like Karl Fischer titration, common sources of analytical error, and key concentration […]
Top titration interview questions often focus on the fundamentals, such as defining titration, distinguishing between the equivalence point and the end point, and explaining various titration types—including acid–base, redox, and complexometric methods. Candidates may also be asked about the principles behind specialised techniques like Karl Fischer titration, common sources of analytical error, and key concentration terms such as molarity and normality. These topics help assess both theoretical understanding and practical laboratory skills.
The process of determining of strength of a solution with the help of a standard solution (of known normality) is called titration.
Normality describes the amount of gram equivalent of compound present in the solution whereas Molarity describes the number of moles present in the solution. For example: The molecular weight of sulfuric acid is 98.079. Hence, it 1M solution will be prepared by dissolving 98 grams of Sulfuric acid in 1000 ml of water whereas the 1N solution of Sulfuric acid will be prepared by dissolving 49 grams of Sulfuric acid) in 1000 ml of water.
The following are the different types of volumetric titration:
Calmagite and Eriochrome Black
Starch solution
Not any indicator. KMnO4 acts as a self indicator.
Crystal violet
Phenolphthalein and Methyl orange are used during acid base titration
Potassium chromate solution
In Iodometry titration, the standard solution of Iodine is used as a titrant whereas, in the Iodometry titration, the liberated Iodine (in the chemical reaction) is titrated with another titrant.
Iodine is slightly soluble in water. But in the presence of iodide ion of potassium iodide, it forms an {I3}–
unstable water-soluble Triiodide anion complex and dissolves quickly👇
That is why Potassium iodide is added during the preparation of 0.1N Iodine solution.
Starch is made of Amylose and Amylopectin.
Amylose is a straight-chain compound, and it gives a blue colour with iodine, and the chain assumes a spiral form. Amylopectin is the branched-chain form, and it adsorbs to form a red-purple colour.
In water, starch gives a water-insoluble complex with iodine. This water-insoluble complex creates problems in detecting the actual endpoint. This means that the endpoint appears before the actual endpoint. That is why the starch indicator is added just before the end point when the colour is pale-straw yellow.
Mastering these core titration concepts is essential for performing accurate analyses and succeeding in technical interviews. By understanding both the theory and the practical challenges, you’ll be well prepared to confidently answer titration-related questions in any analytical or pharmaceutical interview.
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