Created by Sana KaussarTitration QuizTitration is a laboratory technique used to determine the concentration of an unknown solution by reacting it with a solution of known concentration. A titrant is added gradually to the analyte until the reaction reaches the equivalence point, which is often detected using an indicator. This method is commonly used in acid-base, redox, precipitation, and complexometric reactions. The titration curve helps in analyzing the reaction and selecting the appropriate endpoint 1 / 30Which of the following statements about the direct titration method in complexometry is true A back titration is always required The metal-EDTA complex must be unstable The reaction must proceed rapidly to completion The indicator must be colorless 2 / 30Which of the following statements about the endpoint and equivalence point in titration is TRUE They are always the same Endpoint is a theoretical point, while equivalence point is observed Equivalence point is the actual completion of reaction, while endpoint is indicated by a color change Endpoint always occurs after the equivalence point 3 / 30Which of the following indicators is commonly used in EDTA titrations Phenolphthalein Methyl orange Eriochrome Black T Bromothymol blue 4 / 30Which of the following titration methods uses back titration Volhard method Mohr method Fajans method Argentometric titration 5 / 30Which type of titration is used to determine the amount of vitamin C in a solution? Acid-base titration Redox titration Precipitation titration Complexometric titration 6 / 30Which ligand other than EDTA is used for complexometric titration? NH₃ cyanide DTPA (Diethylene triamine pentaacetic acid) sulphate 7 / 30Determination of metal in an alloy can be found easily by acid base titration complexometric titration redox titration precipitation titration 8 / 30What is the main principle of the Fajans method of precipitation titration? Formation of a colored precipitate Use of an adsorption indicator Formation of a soluble complex Use of acid-base indicators 9 / 30The color change at the endpoint of an EDTA titration using Eriochrome Black T occurs because of Precipitation of the metal ion Formation of a colored metal complex Liberation of hydrogen ions Change in oxidation state 10 / 30What is the major limitation of the Mohr method? It cannot be used in acidic solutions It requires a colored indicator It is only applicable to sulfate ions It requires an external indicator 11 / 30The conditional stability constant (K') of a metal-EDTA complex is dependent on Temperature only pH and free ligand concentration Buffer concentration only Indicator concentration 12 / 30Which of the following conditions is required for the Mohr method to work accurately Acidic medium (pH < 4) Neutral to slightly alkaline medium (pH 6-9) Strongly basic medium (pH > 12) Any pH can be used 13 / 30The titration of Zn²⁺ with EDTA is best performed at what pH? 3 7 10 13.3 14 / 30Which of the following metals does NOT form a stable complex with EDTA? Ca²⁺ Mg²⁺ Fe²⁺ Na⁺ 15 / 30Which of the following titrants is used in Volhard’s method AgNO₃ NH₄SCN NaCl K₂CrO₄ 16 / 30Hardness of water can be found by which titration acid base titration complexometric titration precipitation titration redox titration 17 / 30What is the function of a masking agent in complexometric titration To enhance metal-ligand complex formation To change the color of the indicator To prevent interference from unwanted metal ions To reduce the solubility of the metal complex 18 / 30Which of the following indicators is commonly used in the Mohr method of precipitation titration Methyl orange Fluorescein Dichlorofluorescein Potassium chromate 19 / 30The endpoint in the Mohr method is indicated by the formation of A white precipitate A red precipitate A yellow solution A blue solution 20 / 30Which of the following conditions increases the stability of a metal-EDTA complex? Lower temperature Decreasing ionic strength Higher pH Higher pressure 21 / 30The stability constant (Kf) of a complex is given by which of the following expressions? Kf=[Metal][Complex] Kf=[Complex]/[Metal][Ligand] Kf=[Metal]/[Ligand][Complex] Kf=[Metal]/[Ligand]2[Complex] 22 / 30In complexometric titrations, why is a buffer used To maintain the solubility of the metal complex To adjust the pH for maximum complex stability To oxidize metal ions To precipitate interfering ions 23 / 30The pH range for the proper working of Eriochrome Black T in complexometric titration is 1-3 3-5 6-8 9-11 24 / 30Which of the following indicators is used in the Fajans method Phenolphthalein Fluorescein Methyl red Potassium chromate 25 / 30In a titration of calcium with EDTA, which buffer is commonly used Acetate buffer Phosphate buffer Ammonia-ammonium chloride buffer Borate buffer 26 / 30The endpoint in a complexometric titration is detected by Precipitation of a metal salt A sudden pH drop A color change of the metal-indicator complex Evolution of gas 27 / 30EDTA is a ......dentate ligand because it has how many donor atoms 2 3 5 6 28 / 30In Volhard’s method, what is the function of ferric ions (Fe³⁺)? To act as a catalyst To prevent precipitation To serve as an indicator To complex with silver ions 29 / 30Which of the following statements about EDTA is incorrect? It forms a 1:1 complex with most metal ions It has four carboxylate groups It has two amine groups It is only soluble in acidic solutions 30 / 30The masking agent used in the determination of calcium in the presence of magnesium is Ammonium chloride Potassium cyanide Triethanolamine Potassium hydroxide Your score isThe average score is 73% 0% Restart quiz
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