Class 12 Chemistry VIVA Questions with Answers

• Important practical viva questions chemistry class 12 for Intermediate part-II students.
• Q. What is meant by chromatography? Ans: "Chroma" means colour and graphic means measurement. So, it is qualitative as well as quantitative measurement of coloured compounds as well as colourless compounds.
• Q. What is principle of chromatography? Ans: The main principle of chromatography is distribution law. In paper chromatography each of solute from mixture of solutes in separated on the basis of solubility and adsorption of different solutes in various solvents.
• Important viva questions for chemistry practical class 12 with answers pdf download for Intermediate part-II students.
• Q. On what principle the separation of mixture of inks by paper chromatography is based? Ans: Different pigments have different solubilities or rates of flow in different mobile phase. The substances having high R, value will be taken by solvent.
• Q. What is distribution law? Ans: A solute distribute itself between two immiscible liquids in a constant ratio of concentration irrespective of the amount of solute added.
• Important class 12 chemistry practical viva questions with answers salt analysis for Intermediate part-II students.
• Q. What is Rf value? Ans:  Rf = Distance travelled by solute (Cm) / Distance travelled by solvent front (Cm)
• Q. What is Chromatogram?
• Ans. The finished paper with the bands of various components obtained as a result of chromafography is known as chromatogram.
• Q. What is eluent? Ans: The solvent used in chromatography is called as eluent.
• Important chemistry viva questions class 12 2025 for Intermediate part-II students.
• Q. What is locating agent? Ans: The spraying agent used to detect the colourless substances on chromatogram is called locating agent. It forms a coloured complex with solute substance.
• Q.9 Why H2S is used as locating agent for Pb2+ and Cd2+ ions? Ans. Pb + H2S → PbS ( Black Spot ).  Cd 2+ +  H2S → CdS ( Yellow Spot ).
• Q. Define common Ion Effect? Ans: "The phenomenon in which degree of ionization of an electrolyte is suppressed by the addition of an other electrolyte containing a common ion is called common ion effect".
• Important class 12 chemistry practical viva questions with answers titration for Intermediate part-II students.
• Q. Define saturated solution? Ans: A solution which cannot dissolve more quantity of solute at given temperature, is called saturated solution.
• Q. Define Solution? Ans: Ahomogenous mixture of solute and solvent is called solution.
• Q. Define Solubility? Ans: The maximum amount of solute dissolve in 100g of solvent at a given temperature to saturate that solution is called solubility of that substance.
• Q. Define Solubility product? Ans: It is the product of concentration of oppositely charged ions in equilibrium state with the solid ionic salt in its saturated solution at a given temperature. It is denoted by K.
• Important viva questions for class 12 chemistry for Intermediate part-II students.
• Q. Which common ion is used for purification of NaCI? Ans: Chloride ion (Cl).
• Q. What is the difference between hydrochloric acid and Hydrogen Chloride? Ans: Hydrogen chloride is a gas in molecular form while aqueous solution of HCl gas is called hydrochloric acid.
• Q. What is table salt or common salt? Ans: Sodium chloride (NaCl).
• Q. What is brine? Ans: Saturated solution of NaCl is called brine.
• Q. Name a chemical compound responsible for hygroscopic nature of common salt? Ans: Magnesium Chloride (MgCl2).
• Q. Why NaCl cannot be purified by the process of crystallization? Ans: Because of its very small difference in solubility at ordinary tempearature and at high temperature 36g at 25C and 39g at 100C.
• Q. What is volumetric analysis? Ans: It is the branch of quantitative analysis which involves the measurements of the volumes of reacting substance.
• Q. What is titration? Ans: The process of determining practically the volume of a solution, which completely reacts with a known volume of other substation is called titration.
• Q. What is titrant? Ans: The solution which is taken in burette is called titrant.
• Q. What is titrand? Ans: The solution which is taken in conical flask is called titrand or titrate.